Home » If Your Car Has A Timing Belt, It’s Not Really ‘Reliable’

If Your Car Has A Timing Belt, It’s Not Really ‘Reliable’

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The legendary Toyota Land Cruiser, the unstoppable XV20 Toyota Camry, generations of Honda Accords, the smooth and trusty Lexus LS — these are often mistakenly considered some of the most reliable cars of all time. I say “mistakenly,” because all of these vehicles are expected to grenade themselves after ~100,000 miles unless you tear their engine apart and spend four figures on a major repair job. That major repair job is replacing a timing belt, a part whose presence — in my opinion — disqualifies any vehicle from being considered truly “reliable.” Here’s why.

I realize this is a smoking hot take that might send Land Cruiser and Honda fans fuming, but it’s actually quite straightforward; it’s time for those of us hypnotized by factory maintenance guidelines to snap out of it. A timing belt does not fall under “regular maintenance” any more than a head gasket swap does (on a pushrod motor). It’s a major job, it’s not cheap, and it should be considered a substantial repair. Because the manufacturer decided to include an unnecessary consumable in the bowels of the engine, a 100 Series Land Cruiser or Camry or Accord has to go into the shop for a $1,300 repair after only seven years on the road; nothing about that is “reliable” (unless we take the word literally — in which case you can reliably expect to lose lots of money every 100,000 or so miles).

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Anyway, I’m getting ahead of myself. Let’s take a step back and talk about what prompted an even spicier edition of David’s Takes (my op-ed that runs every Sunday) than last week’s “It’s Time To Stop Hating On Fancy Pickup Trucks.” A few years ago, I was the proud owner of a 2001 Lexus LX470 — the Lexus version of the 100 Series Toyota Land Cruiser. The vehicle is, almost universally, considered to be one of the most reliable SUVs of all time. You’ll see it on safaris in Africa, on 15,000-mile overlanding trips through South America, and bouncing all over the Pacific Northwest and on Rocky Mountain trails; the 100 Series Land Cruiser is rough-and-tumble, and the vast majority of its reputation has been built on its longevity.

The Unstoppable Land Cruiser Is Stoppable. Every 90,000 Miles

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My 2001 (shown above) had 265,000 miles on it and ran beautifully. It towed my Jeep Forward Control across the country while keeping the Lexus’ cabin almost perfectly silent; the LX was really a no-bullshit SUV for me, and I enjoyed driving it.

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But as I wrote more and more stories about my adventures in that vehicle and read comments from Toyota fans stating how unstoppable that 4.7-liter V8 is, I decided to do a bit more research into the smoothest V8 engine I’d ever heard, and that’s when I spotted this in the Scheduled Maintenance Guide:

Replace Belt Schedule

 

This changed my whole perception of the motor.

This engine, known to be one of the most reliable of all time, has to have its timing belt changed every 90,000 miles. Since the average American drives around 13,000 miles per year, that means the belt has to be swapped every seven years. That’d be like buying a 2017 car today with 90,000 on it, and then the engine blowing up. Would anyone call that a reliable engine? No.

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But that’s what could happen if you forewent that timing belt job.

For those of you who don’t know, a timing belt is what connects the rotation of the crankshaft — which dictates the position of the pistons in their cylinders — to the camshafts, which dictate the positions of the intake/exhaust valves for each cylinder. It’s extremely important that the timing of the valves relative to each piston’s position in its stroke is precisely managed.

With a cylinder’s exhaust valves shut, the intake valves have to open as the piston goes down to suck in air; intake valves have to close as the piston moves back up to compress that air charge; both sets of valves have to remain shut as the piston is shot down during its combustion stroke; and then the exhaust valves have to open as the piston rises to expel its exhaust, ultimately out of the tailpipe.

If the valve timing — which is set by the timing belt spanning the sprockets at the ends of the crankshaft and camshafts — is altered, and, say, the intake valves are open when the piston rises up during its exhaust or compression stroke, the piston can hit the valves and destroy them. This could require a major engine repair. This happened to my colleague Jason.

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It’s Too Risky To Skip 90,000 Mile ‘Service.’ But It’s Not An Easy Job

Jason owns a VW Tiguan 2.0T; when the car was 10 years old with 120,000 miles on the clock, its engine blew up (the pistons hit the valves and bent them) because the timing chain failed (see video above). Google “VW Tiguan timing chain failures” and you’ll see that this is a rampant problem that has, in many people’s eyes, ruined the first-gen Tiguan’s reputation. Meanwhile, the Toyota Land Cruiser and my old 1995 Honda Accord and various Toyota Camrys behave in exactly the same way; after 10 years or 120,000 miles, their timing systems can fail (their belts snap), and the interference engines can grenade themselves. And yet, these vehicles have a great reputation while the Tiguan doesn’t. Why? Simply because Toyota/Honda writes in their manual that the timing belt is a maintenance item? So all VW had to do it write in its service manual: “Replace timing chain at 90,000” miles and the Tiguan’s rep would have been saved?

Does this mean that all GM had to put in the Saturn Vue’s service manual was “replace JATCO continuously variable transmission at 120,000 miles” and the car would have a sterling reputation? All Subaru had to write in its service manuals is “replace head gaskets at 90,000 miles” and it’d change the way people see Subarus?

On some level, the answer is “yes,” because knowing when things are about to fail is pretty darn valuable. These cars with timing belts tell you: “Your engine is about to fail. Take it in to have the engine serviced,” and that’s useful. Having a transmission or head gasket or timing chain fail suddenly and unpredictably makes driving a car miserable. I’m also being a little facetious, because swapping a transmission, timing chain, and even a head gasket is typically harder than changing a timing belt, but still! It’s not like changing a timing belt is easy; it’s a job! (One that I’ve done too many times).

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On the Land Cruiser — which is among the easier vehicles on which to swap out a timing chain, as it has a longitudinal engine layout —  you’ve got to drain the cooling system, remove the radiator, take apart the accessory drive, undo the crankshaft pulley (which usually requires a HUGE breaker bar), and on and on. Some novice wrenchers say the job takes them 10 hours, though some who have done it before seem to be able to do it in half that time. Either way, it’s rough.

‘You’ve Got To Be Kidding Me’

Check out the video above and listen to this quote by YouTuber “The Car Wizard.” In the background is a relatively new Honda that needs a timing belt. The Car Wizard discusses a typical interaction with an owner who has to have this “service” done:

“So [customers] call up and say ‘How much is it gonna cost to do my timing belt service?’ And I look it up and figure it all up and I say ‘It’s gonna be $1300.’ And I hear the phone hit the ground. And they pick it back up and they’re like: ‘You’ve got to be kidding me!'”

That owner’s response makes perfect sense. Here’s this car known for its reliability, and it has to have a $1,300 engine service done every seven years. Meanwhile, many cars with timing chains have to do nothing. Zero. Nada. Timing chains and their guides/tensioners — if properly designed (Jason’s Tiguan proved that not all of them are) — are meant to last the entire life of the vehicle. In the case of a pushrod engine, they pretty much never fail, and engines with timing gears? Even better.

Well-Designed Timing Chains Never Have To Be Replaced

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So coming back to my Land Cruiser — it has a great, buttery-smooth and torquey engine, and I love how it makes oil changes and other basic maintenance easy. But the reality is that, by the time I got rid of the vehicle, its engine was due for its third timing belt replacement. That’s three times $1,300 — almost $4,000 to do something that, in my view, you should never have to do in the first place.

Why would I ever consider an engine reliable when it needed $4,000 in repairs done to it to get to 270,000 miles? My Grand Cherokee above, which had similar mileage, almost certainly never needed a new timing chain. Granted, it wasn’t an overhead cam design (meaning the cam and crankshaft are quite close, so the chain is tiny), but the point is, if an engine requires a new timing belt every seven years, then I’m just never going to consider it reliable. I could have bought an entirely new engine for my Jeep and still come out ahead over the Land Cruiser 4.7-liter V8’s timing belt jobs.

In my view, a reliable engine is one that’ll do 250,000 miles with basic maintenance. A good example is the Mazda MZR 2.5, also called the Ford Duratec 2.5; it’s a four-cylinder with a timing chain, and because it’s so well designed, the engine requires only basic maintenance. Basic. That means oil changes, maybe some new things on the accessory drive like the alternator or water pump, some filters here and there, new plugs, maybe a few ignition coils, and that’s about it. These are all relatively cheap and easy things to swap. A timing belt is not.

Compare a Honda F22B, which requires a pricy timing belt swap every 7 years to a Mazda MZR 2.5, which requires oil and filter changes, and you’ll understand why I consider the latter the truly reliable motor.

To Be Sure…

To be sure, timing belts can last longer than 90,000 miles (though some are expected to be changed at 60,000 miles). Heck, some have had them last 150,000 miles or more. But the reality is that the risk of blowing up the engine is too high, and this leads most folks to follow roughly the recommended service schedule. It’s also worth noting that Toyota Land Cruisers are known to survive timing belt failures, so even if you were to try to stretch that change out to 150,000 miles, there’s a chance that if the belt snaps, the engine will be fine. (Still, in general, timing belt failures in interference engines can often lead to bent valves or damaged pistons; it’s not worth risking it).

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It’s also worth mentioning that, while The Car Wizard’s $1,300 quote does line up with typical timing belt jobs you see posted to the web (especially recently, as labor rates have skyrocketed in the past few years), historically it’s been possible to do a timing belt at an independent shop for $600 to $700.

It’s also worth mentioning that some timing belts are easier to change than others. But I’ve done the job a few times, and it’s never been remotely fun. It’s easier to swap a head gasket on my Jeep 4.0.

Anyway, there’s a reason why timing belts are pretty much gone from modern engines. Expecting such an intensive and expensive service every seven or so years is just ridiculous. The weight/noise/cost reduction just isn’t worth it. As you can see in this table, Toyota has moved on from the clearly inferior technology:

I try to avoid engines with timing belts. In my eyes, they’re just not worth the worry, especially if it’s not clear when the latest belt-change was done. This isn’t a concern for a well-designed timing-chain engine.

Image credits: Toyota, Genems Systems via YouTube screenshot

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Baron Usurper
Baron Usurper
2 months ago
Reply to  David Tracy

I’m loving these articles DT! (serious)

J Money
J Money
2 months ago
Reply to  David Tracy

It’s so weird how mad everyone gets (I know, this is the whole point of comments/replies on the internet) when they hear an opinion that is different from their own. And in this case, it’s backed up by facts….you can love your timing belt time bombs, people — but the fact remains that they’re time bombs.

Bjorn A. Payne Diaz
Bjorn A. Payne Diaz
2 months ago
Reply to  J Money

The problem is his opinion is in theory. Most of the replies, mine included, are in practice. In practice the opinion is chains suck because of poor implementation. He can certainly have it, but it’s kind of like saying I’d be cute if I wasn’t so fucking fat.

Bjorn A. Payne Diaz
Bjorn A. Payne Diaz
2 months ago
Reply to  David Tracy

I know. I shouldn’t have said it that way. Apologies. All else Chains are better than belts yes. Modern implementation of chains I don’t like as the OEMs are cheap and belts are cheap enough to make them good and chains are pricey and lead to cost cutting and failure.

That said, I find it interesting that although they don’t have nearly the market share as chains, belt driven bicycles are far more reliable even in single speed form than chain driven bicycles. Now, a difference is you need a special frame (or to cut yours!) to use a belt drive on a bicycle.

Bizness Comma Nunya
Bizness Comma Nunya
2 months ago
Reply to  David Tracy

David, I feel like it’s not really the issue of the points you make in the article, but more of the issue of using the word “unreliable” in comparison to timing belts, and then using images of a Honda Accord, Toyota Camry, and 100 series Land Cruiser/LX. Three vehicles known for their reliability, unless you skip the timing belt service interval, and/or cheap out on parts (i.e. not paying for a new tensioner(s)… that’s the owners, and maybe the technicians fault.

Doing a timing belt service isn’t fun, some are really easy (i.e. Ford Pinto Motors in Rangers) some look to be a fucking nightmare (Ferrari 360 Modena).

However, timing belt service IS part of routine maintenance. If you don’t want to buy a car with a timing belt, that’s understandable. But I feel like you should respect reliable cars that did use belts as, what they are…reliable cars. Much like the cheap Sienna you purchased that made it to >230k miles on a timing belt system, maybe it was even the original belt? Probably not though…

Side-note: go ahead and search the internet for what owners are saying about their timing chains (and associated hardware) needing replacement on Ford 3.5/3.7Ls (ecoboost or not), GM 3.6Ls, VW/Audi I4’s/V6’s/V8’s, various BMW motors, JLR V8/V6 post-2009, etc…

MOPAR switched from a belt drive SOHC to a chain drive DOHC arrangement going from the 3.2/3.5L to the 2.7L…. and we all know the 2.7L is garbage vs. it’s close relatives.

Why am I so adamant (borderline being a turd) about this issue? If you were a dealer tech (or independent) who got paid to work on enough OHC motors with timing chain issues, and stupid timing chain designs, I promise you, you would understand my position better.

I hope you feel that you aren’t being attacked, because that’s not cool. And at the end of the day, it’s all just opinions, and a matter of preference.

david kenney II
david kenney II
2 months ago

I agree with you and have done the chain replacements on some of these vehicles. unfortunately there may be an audi 4.2 chain service in my future, (customers car, not mine).

Bizness Comma Nunya
Bizness Comma Nunya
2 months ago

Yikes…sorry to hear that. Unless it pays good flat-rate and you’ve done it before so you know how to do it quicker?

Would you rather have to do the timing belt service on an older Audi 4.2 V8?

Col Lingus
Col Lingus
2 months ago
Reply to  David Tracy

Good story DT. Thanks. Learned my lesson about 35 years ago. No more timing bels ever. Never had a big issue, but I refuse to buy another car with a timing belt.
Thanks again.

MP81
MP81
2 months ago
Reply to  David Tracy

Tell that to Audi S4 owners with timing chains on the back of the engine, against the firewall that definitely requires service.

Ok_Im_here
Ok_Im_here
2 months ago
Reply to  David Tracy

As a Honda Odyssey owner, I’ve been waiting for someone to say this. I love this minivan, but this is the thing I literally have to bank money for. And I know a few people who have said “we had all kinds of serious engine problems with ours” and the first question out of my mouth is, “did you do the schedule timing belt and transmission fluid changes?” Honda’s are particularly finicky about both. I swear the only reason why the timing belt is there is because Honda makes money on it.

Anonymous Person
Anonymous Person
2 months ago
Reply to  David Tracy

We just bought the new 2024 Trax LS with the 1.2L Turbo 3-cyl. The owner’s manual says to change the timing belt and oil pump at 150,000 miles. Of course, you never have to touch the transmission fluid (6-speed auto) for the life of the car (transmission) unless it’s used in a “severe duty” application.
Our local stealership included the “Warranty Forever™ program in the MSRP of the vehicle. As long as I bring it to the stealership (or any certified service center if I call a toll-free number and let them know first) for all scheduled maintenance and promise to never personally do any oil changes or scheduled service on the vehicle, they will, in turn, cover the entire powertrain from the turbocharger all the way to the front wheel bearings for the life of the vehicle or until the cost of the repair exceeds the NADA book value of the vehicle.
I’m skeptical, but does this make it more “reliable”?

Smoke&Mears
Smoke&Mears
2 months ago

A medium hot take in my judgement. You are on to something. If, even after having done all required maintenance, a vehicle cannot be trusted to operate then it is unreliable. Reference just about any DDM vehicle as we all know. The opposite being true, what the Toyota 2UZ interference valvetrain & timing belt combine to give us is a reliable motor that is moderately expensive to maintain… and very durable as well.
But yeah gears would be rad.
Also, I’ve owned quite few belt driven Ducati. Neither reliable nor durable!.

Rust Buckets
Rust Buckets
2 months ago
Reply to  Smoke&Mears

But you can trust many timing belt engines, like the Toyota v8s, to be reliable if you’ve done all required maintenance. David is just complaining about the expense and depth of that maintenance.

Lockleaf
Lockleaf
2 months ago
Reply to  Rust Buckets

I trust my Subaru engine to go for another 80K after I do the head gaskets. So is it just the definition of maintenance then?

Rust Buckets
Rust Buckets
2 months ago
Reply to  Lockleaf

David mentioned that point. Yes, that is just the definition of preventative maintenance. It’s maintenance that isn’t a good thing and that nobody wants to do, but if you do it routinely and preventatively then I’d call it maintenance.

P161911
P161911
2 months ago

Timing GEARS! One of the many reasons that the Ford 300 I-6 is considered indestructible.

Ecsta C3PO
Ecsta C3PO
2 months ago
Reply to  David Tracy

No David, the big fan goes behind the radiator

James Carson
James Carson
2 months ago
Reply to  P161911
StillNotATony
StillNotATony
2 months ago

The Ford 300cid straight six would like a word with you, DT. Timing GEARS FTW!!

Mr. Canoehead
Mr. Canoehead
2 months ago
Reply to  StillNotATony

And the Cummins 6BT….but some have the killer dowel pin that drops into the gears.

Rust Buckets
Rust Buckets
2 months ago
Reply to  Mr. Canoehead

Most diesels have timing gears, the Cummins, the Ford IDIs and Powerstrokes, and I believe all Duramaxes.

P161911
P161911
2 months ago
Reply to  StillNotATony

You beat me to it.

Jnnythndrs
Jnnythndrs
1 month ago
Reply to  StillNotATony

So would the venerable IH V8’s of old(304/345/392) One of the reasons they lasted virtually forever(the other being that they didn’t make enough power to hurt themselves).

Also, the old Cologne 2.8 V-6 used in innumerable Capris and Rangers used gears, but they went to a chain with the 2.9.

MrLM002
MrLM002
2 months ago

Historically at least engines with timing belts were non interference. I’d much rather have a broken timing belt on a non-interference engine than a broken timing chain on an interference engine (which more often than not means a full engine rebuild best case, new engine worst case).

I had an alternator belt go on me on my 94 Toyota Pickup with the V6, and we thought we could just pop a new one one. Well after we got all the bits of broken belt out of the engine bay we realized that the water pump and the power steering pump were driven by belts and both of those belts were in front of where the alternator belt would go along with the fan belt. So I scheduled an appointment with a local auto chain to replace all of the belt (including the timing belt since you gotta take all the other belts off to get access to the timing belt).

During the whole time I was dealing with that I thought to myself how much easier it would have been to work on my truck if I didn’t have power steering, a water pump, etc.

Honestly I’m pretty sick of complex shit that I’m stuck fixing. I understand simplicity has lots of disadvantages, but it sure as shit saves a lot of time and troubleshooting.

I’m probably going to buy an old Smithco Red Ryder and turn it into a moped and or weld myself up a knockoff of one. I’m sick of complex BS that sucks up my time.

TOSSABL
TOSSABL
2 months ago
Reply to  MrLM002

On my final EA Subaru, I had removed AC & PS —along with all emissions (wouldn’t do that now, mind: broke-ass single dad at the time)—and doing the double timing belt alone took less than an hour from lifting hood to starting motor. I had, of course, done them a few times by then.
With all accessories & factory emissions, it was more of an afternoon even when familiar.

Slow Joe Crow
Slow Joe Crow
2 months ago

Conversely a timing chain does not guarantee reliability. I Do Cars has lots of engines with timing chain failures of various types. I also had several water cooled VWs that had very reliable belts that were cheap and easy to change. I also had a Ford Escort that spit the rubber insert out of the crank pulley every 57k miles si I had the timing belt done because it had a 60k change, in the oughts that was a #2-300 job. Timing belts have apparently gotten harder and more expensive to replace and occasionally gotten dead stupid like the wet belt in the 1.0 Ecoboost.
Gears are still the ultimate in reliability

Bizness Comma Nunya
Bizness Comma Nunya
2 months ago
Reply to  Slow Joe Crow

Agreed… welt belts are dumb. It’s not just the timing belts. Newer Ford 5.0L V8’s, 2.7 Ecoboosts, 1.0L, 3.0L duramaxes….all have wet belt oil pump drives. Are they bad? Not really, but the concern is the oil degrades the belt over time, and to replace the tiny wet oil pump belt isn’t really going to be super easy, even when the rest of the engine has chain(s).

Echo Stellar
Echo Stellar
2 months ago
Reply to  Slow Joe Crow

So true! I Do Cars has some of the best reference material for true durability.

Space
Space
2 months ago

#1 it’s to save money
#2 My guess is any manufacturer using timing belts wants their vehicle to fail, but only on the 3rd owner after ~120,000 miles they could care less about that owner and it helps to drive more sales.

Rust Buckets
Rust Buckets
2 months ago
Reply to  Space

You think 80s Toyota and Honda wanted their vehicles to fail after 120k miles?

If that is in fact what they wanted, it didn’t work

Space
Space
2 months ago
Reply to  Rust Buckets

You are right that doesn’t really sound like 80’s toyota/Honda, or 90’s or 00’s…

Cheap Bastard
Cheap Bastard
2 months ago
Reply to  Space

Clearly Toyota learned nothing from NUUMI

Jason Smith
Jason Smith
2 months ago
Reply to  Cheap Bastard

GM did their best, but Toyota was just too damn set in their ways…

R.Z.
R.Z.
2 months ago

I agree with David 100%. While timing belt maintenance schedule can be mostly adhered to by somewhat knowledgeable motorists, and could be seen as a good but achievable DIY challenge by enthusiasts (I did timing belt and tensioner myself on my first car Alfa 75 during college), it’s just too much a potential car-stranding disaster for general public with zero chance of detection before failure, which is never a good thing in FMEA. It think that’s why most OEMs moved away from belts to chains depite belt’s advantage in cost, complexity and NVH, etc.

BolognaBurrito
BolognaBurrito
2 months ago

Just wait till my two-stroke V8 is ready… no valves to time at all!

MrLM002
MrLM002
2 months ago
Reply to  BolognaBurrito

Same thing with many 2 stroke diesels!

I wish someone made a 50cc 2 stroke diesel, it would make for a great moped engine

Rust Buckets
Rust Buckets
2 months ago
Reply to  MrLM002

Which two stroke diesels? Any two stroke diesel that isn’t the Detroit Series 71/53/92 is an exceptionally rare thing, and those have valves.

MrLM002
MrLM002
2 months ago
Reply to  Rust Buckets

In the US perhaps

Michael Beranek
Michael Beranek
2 months ago

David, you just made a case for the 3800.
That being said, an OHC in-line engine with a simple up-and-down chain is pretty reliable. Make it a vee and add a ton of convoluted craziness (I’m looking at you, Audi) and it’s not reliable at all.

Rust Buckets
Rust Buckets
2 months ago

Made a case for the 3800? Because it has a very normal and average timing chain and pushrods?

Michael Beranek
Michael Beranek
2 months ago
Reply to  Rust Buckets

Yup, it’s designed to last the life of the engine, and the water pump is completely separate.

Rust Buckets
Rust Buckets
2 months ago

I have never understood why people single out the GM 3800 as an especially reliable engine when all of the attributes that are supposed to make it reliable are in common with contemporary Ford and Chrysler transverse V6s.

Michael Beranek
Michael Beranek
2 months ago
Reply to  Rust Buckets

Because neither of those companies ever made a V6 as good as the 3800. GM also didn’t, the 60-degree 3900 was too complicated for it’s own good.

Rust Buckets
Rust Buckets
2 months ago

There are Ford and Dodge engines that are known for being decently reliable and long lasting, and they share 100% of the attributes that are supposed to make the 3800 special: iron block, pushrod, honestly I don’t know what else. Basically, there is nothing about the design of the 3800 that makes it special but people act like there is.

Dodge minivans with that transverse V6 routinely last to pretty high mileage, and I’ve had good luck with a couple.

Michael Beranek
Michael Beranek
2 months ago
Reply to  Rust Buckets

Again, those engines simply aren’t as good. Just like some DOHC inline fours are better than others.

Camp Fire
Camp Fire
2 months ago
Reply to  Rust Buckets

Ford’s contemporary 3.8L Essex V6 is legendary in its unreliability. Preventative head gasket replacement every 60,000 miles. And often paired with a transmission from the troubled AXOD family.

Having owned both, I much, much prefer the GM 3800/4T65 combination.

Boulevard_Yachtsman
Boulevard_Yachtsman
2 months ago

I’ve never been a fan of timing belts, but now that I’m thinking about it chains haven’t been all that good to me either. I’ve had to replace three of them in different Cadillacs due to GM’s asinine habit of using nylon over pot metal for it’s timing gears.

Picked up an XK8 last summer and I’ve now learned that car has 4 timing chains I need to replace to make it “reliable” (well, as reliable as one can hope for on a 24 year old Jag).

In fact, it seems that belt changes in some vehicles may extend their reliability, since the water pump is usually replaced at the same time. I’ve definitely witnessed as a few cars make their way to an early grave because of overheating due to a water pump failure.

Last edited 2 months ago by Boulevard_Yachtsman
Boulevard_Yachtsman
Boulevard_Yachtsman
2 months ago
Reply to  David Tracy

Hello wife’s ’95 Escort with the 1.9L. The timing belt kit actually included a water pump. The saving grace there was that I think everything grand-totaled around 60 bucks.

Rust Buckets
Rust Buckets
2 months ago
Reply to  David Tracy

What’s wrong with the water pump being driven by the timing belt/chain? It means the water pump keeps going if you lose the fan belt, which I don’t mind.

Mike Smith
Mike Smith
2 months ago
Reply to  Rust Buckets

The biggest problem that I know of is that if the water pump fails, the coolant leaks into the timing cover and down into the crank case, rather than leaking on the floor. So your first indication you have a bad water pump is a low oil pressure light because the oil in the sump has been churned into the Forbidden Milkshake and now all your bearings are junk…

Jason Smith
Jason Smith
2 months ago
Reply to  Mike Smith

Out of curiosity, what engine are you talking about where the water pump could leak coolant into the crankcase? Every timing belt engine I’ve worked on had the timing assembly (including the water pump) effectively outside the engine and only covered by glorified dust covers. I just kind of assumed that was the way it was for the very good reason you mentioned.

Last edited 2 months ago by Jason Smith
Mike Smith
Mike Smith
2 months ago
Reply to  Jason Smith

Notably, the tranverse applications of the Ford 3.5/3.7 liter V6 are (were?) this way.

https://bobistheoilguy.com/forums/threads/dreaded-ford-3-5l-3-7l-water-pump-how-to-extend-the-life.322514/

Fortunately for me, as an owner of a rear wheel drive application of the 3.7 V6, those engines have traditional belt driven external water pumps.

Jason Smith
Jason Smith
2 months ago
Reply to  Mike Smith

You know what, I misread your comment (I even read it a couple of times and didn’t catch it). I thought you were referring to timing belt driven pumps instead of timing chain driven water pumps.
I can totally see what you meant by a chain driven water pump being a MAJOR potential problem, and you can probably understand my confusion when I thought you also meant the same with timing belt driven water pumps. What can I say, it was Monday morning…

Last edited 2 months ago by Jason Smith
Rust Buckets
Rust Buckets
2 months ago
Reply to  Mike Smith

If it’s driven by the chain yes. Belt no.

That makes sense, I’d never thought about that. Not that water pumps leak that often.

Mike Smith
Mike Smith
2 months ago

Is GM still doing that plastic timing sprocket nonsense? I thought they learned their lesson after the bakelite timing gears shearing off teeth in the 70’s…
My ’78 Mercury with the 351 Windsor had a similar setup, but at least Ford molded the plastic over as sheet metal core – the plastic teeth still sheared off, but the sheet metal core of the sprocket held in there so that I had time to notice the sound of the timing chain hitting the inside of the timing cover and was able to fix it before it gave up and skipped time. The OG GM sprockets were pure plastic and didn’t give you that grace period.
Of course the domestic OEM’s found a way to make one of the most reliable possible timing drive systems unreliable…

P.S. They claimed that the plastic gears were meant to improve NVH, but I can tell you that is a bunch of nonsense; I replaced the timing set with a double roller timing set, and noticed zero increase in noise from the engine.

Boulevard_Yachtsman
Boulevard_Yachtsman
2 months ago
Reply to  Mike Smith

I certainly hope not, but can’t say for sure. Personal experience with a Cadillac Brougham having the Olds 307 engine tells me that they did this at least through 1990.

Ham On Five
Ham On Five
2 months ago

So … How long is an EV battery expected to last before the vehicle is bricked? And what’s the cost of its replacement?

VanGuy
VanGuy
2 months ago
Reply to  Ham On Five

I’d be really surprised if a dead battery “bricked” an EV, like made it so that it could never be used ever again, even with a new battery.

….and, what’s your point? We’ll learn more and more about EV longevity as more come on the road and get older, batteries might come down in price as technologies change (or not! Who knows what the future brings)…

And either way, this is about timing belts, which EVs don’t have. Do you have a comment on timing belts?

Ham On Five
Ham On Five
2 months ago
Reply to  VanGuy

I prefer timing suspenders.

CantoDrifto
CantoDrifto
2 months ago

Reliability and durability are often used interchangeably, but they are different concepts.

Reliability is for every 10000 drives, how many times the car runs into an issue.

Durability is how many drives before things start to wear out and need replacement.

In this case, the timing belt is a durability issue, and the effort to move to chain in newer engine is an attempt to improve durability.

The Toyota V8 earned it’s reputable as a reliable engine because it doesn’t leave the driver stranded often, but timing belts are not as durable as timing chain is also generally true.

But saying an engine is not reliable because it is not durable is where the take went wrong.

Last edited 2 months ago by CantoDrifto
Thirdmort
Thirdmort
2 months ago
Reply to  CantoDrifto

Thank you! Finally someone using the right terminology. I’d just call this being a high maintenance, but reliable engine, but your wording is perfect!

CSRoad
CSRoad
2 months ago

Who knew you had to change the oil?

I remember the nylon coating on the 70’s SBC cam sprocket that was prone to breakup at less than 100,000 miles. The Bendix silent timing chain would hit the cover and you knew it was replacement time. I you ignored it it would eat through the timing cover. It worked for the warranty period of 5 years/50,000 miles, therefore I wouldn’t say it was a design failure.

SonOfLP500
SonOfLP500
2 months ago

“…a reliable engine is one that’ll do 250,000 miles with basic maintenance. Basic. That means oil changes, maybe some new things on the accessory drive like the alternator or water pump, some filters here and there, new plugs, maybe a few ignition coils, and that’s about it.”

That is the exact description of our JDM Toyota Noah, 420,000km (260,000 miles) minus a recently blown radiator.

notoriousDUG
notoriousDUG
2 months ago

And the idea that any engine can go 200k in the original timing set is wishful thinking.
Even cam in block that kind of mileage is going to see timing variations that effect performance and cause issues with distributor shaft and gear issues.

Rust Buckets
Rust Buckets
2 months ago
Reply to  notoriousDUG

Umm…… Tons, and I mean tons, of engines are at 200k+ with the original timing set and performing great with no excessive slop. Gear drive timing sets on light diesels often exceed 300-400k miles with zero slop, and heavy duty diesels very frequently exceed a million miles with 100% original internals, including the timing set.

This is a really really bad and misinformed take right here.

notoriousDUG
notoriousDUG
2 months ago
Reply to  Rust Buckets

OK, so I have owned multiple high mile timing chain motors that started to slap the cover before 200k.
Loose timing chains causing timing issues is very much a thing on light diesels. The 6.2/6.5 did it and the 7.3 did it. The ones that go longer have timing gears as you mentioned. The same goes for heavy diesel engines.

I should have excluded gear-timed engines but did not think anyone was that pedantic. And I will tell you right now those million-mile engines have had new parts put in them; I cannot think of an OTR engine I have seen with that kind of mileage that has not had at least an in-chassis done.

Rust Buckets
Rust Buckets
2 months ago
Reply to  notoriousDUG

7.3s most certainly don’t get timing chain slap. Because both the IDI 7.3 and the Powerstroke 7.3 use only gear drive timing.

I have seen plenty of million miles engines that have not had any kind of in frame, often haven’t even had any covers off. I don’t know why you think gears and a cam couldn’t last a million miles.

notoriousDUG
notoriousDUG
2 months ago
Reply to  Rust Buckets

You’re right I am apparently thinking do some other engine I cannot think of.

I cannot believe there are engines that hit a million miles without even an injector change or zero internal issues.
Maybe they are out there but that has not been my experience.

Pappa P
Pappa P
2 months ago
Reply to  notoriousDUG

A million miles is pretty much a vehicle’s lifespan for us. During that time, an engine replacement is scheduled for each unit. Honestly, I don’t think they all get done, and the engines being removed are generally running perfectly at 500,000 miles.
Injector and other failures happen, but they are somewhat rare.
These engines are not dead reliable, but a million miles is doable IMO.
As for your original point, any modern Toyota engine can do 200k on the original timing set, and in most cases another 200k.

Spikedlemon
Spikedlemon
2 months ago

I dont think I understand your rant.

Ducati suggests changing the timing belts every 20k km (~12k miles) or every two oil changes. My local shop also suggests that I check the flywheel bolts at every oil change, and to accelerate the oil changes to every 3000km rather than 10000km per the mfg – with belts every two years (regardless of mileage). Even Gates, the mfg of the belts, notes that their life is a maximum of 8 years.

(Honda motorcycle ownership has none of this absurdity.)

A 100k mi belt change interval sounds divine.

CSRoad
CSRoad
2 months ago
Reply to  Spikedlemon

Ducati has recently pushed the belt service on most of their engines to 5 years and valve service to over 20,000 miles on some.

My only Ducati had a bevel gear cam drive.

Too bad 2 strokes are enviro-hazards they at least were simple.

Spikedlemon
Spikedlemon
2 months ago
Reply to  CSRoad

Im sure I’m jaded, but I don’t trust Ducati enough that they’ve gotten more than twice as good.

Rust Buckets
Rust Buckets
2 months ago
Reply to  Spikedlemon

6000 mile oil change interval on a sportbike? I have no idea what’s typical, but that seems long for such a high strung engine.

Spikedlemon
Spikedlemon
2 months ago
Reply to  Rust Buckets

I’ve had ranges on motorcycles from 3000 to 8000 miles / 5000 km to 12,000km for oil changes on motorcycles. They all, however, align that it needs to be changed once a year minimum.

Many people don’t put on a lot of mileage on a motorcycle so I suspect time is the first thing they hit. I change it at the end of winter, and again end of summer: I figure I can safely not pay attention to mfg guidelines and feel much better.

notoriousDUG
notoriousDUG
2 months ago

You’re grand Cherokee isn’t over head valve?

Yeah… About that. Maybe you should rethink your take if you think that.

Rust Buckets
Rust Buckets
2 months ago
Reply to  notoriousDUG

Oh no. I already called you dumb in your other comment, and now it’s very clear that you have a poor understanding of the subject at hand here.

notoriousDUG
notoriousDUG
2 months ago
Reply to  Rust Buckets

For the record young DT called it overhead valve and then edited the article.

Rust Buckets
Rust Buckets
2 months ago
Reply to  notoriousDUG

Gotcha, my bad

James Carson
James Carson
2 months ago

The wizard does a great one on BMW chains and guides. He is not a fan of BMW and Mercedes to say the least.

Lardo
Lardo
2 months ago
Reply to  James Carson

Had a new 1988 BMW 325 iX. Great car. Just after the warranty ended the timing belt went. BMW rep told me that due to the higher ozone levels in L.A. the belt had failed. That didn’t seem like a legitimate reason to me. After some discussion they covered all the work under good will, except somehow they got me to pay for the new water pump.

James Carson
James Carson
2 months ago
Reply to  Lardo

A good friend had a similar experience with his M5. The tech changing the oil screwed up somehow and the engine lost all the oil and blew up. BMW fought to the last with BMW corp covering the engine and the dealer after much wrangling the labor. They tried to charge him for an oil change on the new engine.

Lardo
Lardo
2 months ago
Reply to  James Carson

that’s funny. they want some kind of token payment

Rust Buckets
Rust Buckets
2 months ago
Reply to  Lardo

Actually, ozone is massively detrimental to rubber, it greatly accelerates dry rotting. It’s not uncommon for the lifespan of tires to be cut in half in areas with especially bad industrial ozone pollution.

Bizness Comma Nunya
Bizness Comma Nunya
2 months ago

Come on dude…. are you really trying to grasp at straws to call timing belts (as a concept) unreliable? Bad take…

Also, if you are calling the Toyota UZ engine “unreliable” by having a timing belt, that’s crazy. I’m not a huge Toyota fan… but you have to recognize good when it exists.

Here’s a hypothetical, you take an immaculately maintained 2001 XJ or 2001 100-series Land Cruiser (UZ engine). Which are you trusting more to drive across, lets say, Africa?

Also, keep in mind that the switch from belts to chains didn’t really increase reliability for certain automakers.

Last edited 2 months ago by Bizness Comma Nunya
Lincoln Clown CaR
Lincoln Clown CaR
2 months ago
Reply to  David Tracy

Is an engine series as a whole reliable if you have to avoid a certain casting?

Rust Buckets
Rust Buckets
2 months ago

Yes

notoriousDUG
notoriousDUG
2 months ago
Reply to  David Tracy

Yeah because 200k plus 4.0s never experience dead lifters… Or sloppy timing chains, or a variety of other problems.

No engine is as reliable as you want the 4.0 to be.

Widgetsltd
Widgetsltd
2 months ago
Reply to  notoriousDUG

I remember 1994-95, when new Jeep 4.0L engines usually had such poor piston-to-bore fit that they sounded like diesels after cold start in winter weather. I carpooled with a guy who leased a new 1994 Cherokee in the Detroit metro area. We drove to work at Chrysler customer relations and talked to customers who were unhappy with their noisy 4.0L engines. They replaced a LOT of engines and bought back quite a few vehicles for that. But hey – the 4.0 will run forever…sounding like a tractor and leaking oil the whole time.

Last edited 2 months ago by Widgetsltd
Alexander Moore
Alexander Moore
2 months ago
Reply to  Widgetsltd

the 4.0 will run forever…sounding like a tractor and leaking oil the whole time.


The Americans aren’t so much for elegance and refinement as they are for charm.

Slower Louder
Slower Louder
2 months ago

Your take seems straightforward to me. I’d like to hear more about the actual reliability of timing chain engines. Are they that failsafe? I seem to remember the Audi’s timing chain is one of humankind’s most complex creations? I’m pretty old, so I am versed in the idea of planned obsolescence, yet I had to get pretty old before I really grasped how many engineering choices in cars are made on the basis of how long the car is supposed to last.

notoriousDUG
notoriousDUG
2 months ago
Reply to  David Tracy

Not without starting to eat distributor gears and shafts they won’t.

Bizness Comma Nunya
Bizness Comma Nunya
2 months ago
Reply to  notoriousDUG

Yeah, even though i agree that guides on a pushrod motor will last a long time (or should). 350k is pushing it.

Raptor
Raptor
2 months ago
Reply to  David Tracy

David— my 2005 xTerra would like a word. Had a supercharger whine for about 50k miles before I finally spent the $1900 to get it fixed. The timing chain guides are plastic and prone to failure, which is what was happening to mine. I think gears are the only true solution

Space
Space
2 months ago
Reply to  Slower Louder

Generally timing chains are reliable on non German vehicles.

Gene1969
Gene1969
2 months ago

The mechanic in my area told me it would be cheaper to replace the engine in my 2011 Ranger that replace the timing chain guides.

Bizness Comma Nunya
Bizness Comma Nunya
2 months ago
Reply to  Gene1969

Ugh… those fucking 4.0L SOHC Ford motors and their dumb timing chains…

Gene1969
Gene1969
2 months ago

Yep.

TOSSABL
TOSSABL
2 months ago
Reply to  Gene1969

I remember reading about those: don’t you have to cut apart the old guide—or maybe it was hack off a boss or something—to remove the original guide? Yet, the replacement is in 2 pieces and can therefore be installed without issue. That kind of planned obsolescence enrages me. The manufacturer saves a minor sum building the vehicle—which also makes long-term service more difficult for the average diy-er.
See also: the growing lack of fuel pump service hatches starting in the 90s in domestic manufacturers. Replacing a fuel pump through the hatch is doable for your average ‘done a couple brake-jobs’ person, whereas removing the tank is much more daunting

Gene1969
Gene1969
2 months ago
Reply to  TOSSABL

Penny pinching and CAD engineering ruins it every time.

Sensual Bugling Elk
Sensual Bugling Elk
2 months ago

A complete four corner brake job (rotors and calipers) easily costs over $1,000 and comes around every 100k miles, just like a timing belt replacement. So do disc brakes make a car unreliable?

Reliability is a state of mind. If your car doesn’t make you 1) constantly think about the possibility of catastrophic failure, or 2) how every mile gets you substantially closer to a massive repair bill, it’s reliable. VW and Subaru engines tend not to meet these criteria. Toyotas do.

I’m also going to spend the rest of the night in a blindingly apoplectic fugue state after reading your disparaging remarks about the XV20 Camry’s engine. The 1MZ-FE is the most glorious production V6 of the 20th century, timing belt and all.

Ham On Five
Ham On Five
2 months ago

And tires come round at 2-3 times as often as brakes …

James Carson
James Carson
2 months ago

I think the point is, that a snapped timing belt on an interference motor will require a motor replacement whereas worn brake pads are annoying and will destroy the rotors. Different order of magnitude in cost.

Widgetsltd
Widgetsltd
2 months ago
Reply to  James Carson

Well, a cylinder head replacement. Bent valves do not usually cause catastrophic piston or cylinder damage.

Last edited 2 months ago by Widgetsltd
Mechjaz
Mechjaz
2 months ago

I think you only alluded to it, but I’m guessing the correction or cure (*cough*except the Tiguan*cough*) is a timing chain?

The idea of a belt, steel belted or grooved or ribbed or whatever, carrying the fundamental mechanical timing from crank to cams has always bothered me. It’s like early in the industrial revolution when leather belts were commonly used and commonly failed in distributing mechanical energy, but in that case humanity was still pending some discoveries in materials science.

In the case of timing belts, the reason to keep belts instead of (generally) vastly more robust chains is a mystery to me. I don’t even like those bicycles driven by strings, even if they’re conceptually neat (with the helpful caveat, oh yeah if it gets wet or dirty it may fail in as few as 500 miles). An engine, especially an interference engine, kept in perfect synchrony by a wear item is no nope no thanks.

Rust Buckets
Rust Buckets
2 months ago
Reply to  Mechjaz

Timing belts aren’t really a wear item, they last a really long time usually. Timing chains don’t always last a really long time.

Manufacturers kept using timing belts because they’re lighter, quieter, cheaper, and simpler.

Pappa P
Pappa P
2 months ago
Reply to  Mechjaz

It’s amazing how factory timing belts can withstand things like high lift cams, obscene rpms, double valve springs, and engines boosted well over 1000hp, and still be perfectly reliable and the right tool for the job.
While they do need periodic replacement, they do a pretty flawless job of keeping an engine properly timed, and chains have no advantage in that regard.

Pat Rich
Pat Rich
2 months ago

I agree, timing belts are dumb. Among all the things the 1uz gifted the 2uz that made it a stout, reliable unit, the timing belt is one of the few annoying ones. Thank goodness Toyota reversed course on that one. What’s funny is that land cruiser before it was chain.

Mike B
Mike B
2 months ago
Reply to  Pat Rich

The 4.5 I6 in the FZJ80? I had the pleasure of driving my buddy’s 93 around SoCal for a few weeks last year. I really liked the character of that engine, it sounded like a tractor on startup, but was nice and smooth, with plenty of torque down low. It was definitely not “quick”, but it cruised at 70 with no problem, and seemed to work less hard maintaining that speed than the 4.0 in my 5th gen 4Runner.

Pat Rich
Pat Rich
2 months ago
Reply to  Mike B

Thats the fella. 351,000 miles on the original chain gear no sweat.

Mike B
Mike B
2 months ago
Reply to  Pat Rich

My buddy’s is just a baby, it rolled 227K miles while I was driving it. He had great timing, he picked it up for 6,500 before prices went crazy. Triple locked.

I want one of these SO bad, but prices these days, yikes.

Andrew Daisuke
Andrew Daisuke
2 months ago

I sold used Volvo’s for a while in the 00’s and one of the huge selling points on a car was “hey, the timing belt has been changed.”

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