The Chevrolet Colorado debuted in 2004 as a perfectly acceptable pickup truck. It could haul a load and get down a trail, but it was perhaps lacking something compared to more rugged, off-road capable vehicles. Only, there’s a way to upgrade it on the cheap if you know where to find the right parts.
Enter the Hummer H3—the smaller, lighter, less famous entry into the road-going Hummer lineup. Unlike earlier models, it was designed by GM instead of AM General, and just so happened to be built on a similar platform as the Chevy Colorado and its sibling, the GMC Canyon (here you can see the frame differences). While the H3 wasn’t as much of a mean military vehicle as the H1 models that came before, and it wasn’t as flashy as the H2, GM still saw to it that the baby Hummer could hack it in the rough stuff. Engineers granted it suspension and drivetrain components that gave it greater capability in tough off-road conditions compared to the more pedestrian Canyon and Colorado whose bones it shared.


And the similarities between the H3 and the mainline GM trucks did not go unnoticed. Eager owners soon discovered that the rugged Hummer parts could provide a bolt-on upgrade to their trucks, offering better off-road performance on the cheap.
Front End

The Hummer H3 first hit the market in 2005. It was designed to trade on the popularity of the Hummer look and name, while nevertheless being smaller and more affordable than the hefty H2 and the crude H1. It debuted with a 3.5-liter inline-five engine good for 220 horsepower, which was paired with a 5-speed manual or four-speed automatic transmission. It was built on a modified version of the GM355 platform that was the heart of the GMC Canyon and Chevy Colorado, which enabled it to slot in neatly to the production lines at GM’s Shreveport truck factory in Louisiana.
While it was a smaller, lighter-duty vehicle than the Hummers that came before, GM was eager to highlight its off-road prowess. The domestic automaker bragged that it was capable of fording 27 inches of water, while it could climb a 16-inch vertical wall and tackle steep grades up to 60%. Eager buyers could kit it out further with chunky 33-inch tires, differential lockers, and other upgrades to further improve its performance in tough conditions.

In contrast, the first-generation Chevrolet Colorado was not such a thoroughbred when it came to the rough stuff. Nor was its sibling, the somewhat upmarket GMC Canyon. GM did offer both two-wheel-drive and four-wheel-drive versions of its new mid-sized truck, as well as an off-road suspension option, but performance off the beaten track wasn’t really the key focus for the model. GM focused on marketing its truck’s blend of utility, on-road comfort, and decent 4×4 capability — with all sharing roughly equal weight. This wasn’t an off-road beast, but moderate off-roading was on its resume.


Naturally, Chevy Colorado owner interested in added capability looked towards the H3.
Forum posts speculated that perhaps the H3’s more rugged front suspension components (independent torsion bar-type, just like the Colorado’s) could potentially fit the more humble truck. Eventually, curiosity turned to experimentation, and the H3 swap was born.

The magic all comes down to the design of the front suspension. Compared to the Canyon, the Hummer H3 boasted a far wider stance with greater travel, thanks to longer upper and lower control arms. Canyon owners realized that by swapping these longer arms on to their trucks, they could get improved suspension articulation, making their vehicles far more capable off-road. The swap would provide other benefits, too, like the bigger brakes that came on the H3. The stock Colorado and Canyon were also infamous for having captive brakes, which meant yanking off the hub to change rotors. Swapping to H3 suspension would provide non-captive brakes and make maintenance far easier.
The H3 swap is primarily for 4×4 models of the Colorado and Canyon, since it’s all about improving off-road performance. To pull it off, you’ll want to grab the upper and lower control arms, along with the knuckles, hubs, brake rotors, calipers, brake hoses, and brackets — ideally off a junkyard truck or a parts vehicle.
Most swappers also tend to go with aftermarket shocks to suit the new setup; this can sometimes require making a little clearance by smacking the Canyon’s bump stop bracket with a hammer. You’ll also need the H3 halfshafts, tie rod ends, and sway bar. There’s also a smattering of bolts and supporting brackets you’ll want to grab to make the swap go smoothly, so it’s important to do your research. Pulling a complete front end off a single vehicle makes it easy to make sure you get all the bits you need.

It looks like the actual installation is relatively straightforward. The first step is to pull off the original Colorado suspension arms, hubs, and brakes, which can be done relatively quickly. From there, it’s just a matter of bolting on the replacement parts piece by piece.
Depending on your exact setup, you may need to make some additional minor tweaks. For example, as noted by YouTube channel Wrench & Chill, you’ll usually need to tap holes in the frame for one of the bolts for the H3 sway bar mounts, since they’re wider than the stock Colorado units. Alternatively, you can buy adapter plates off the shelf. You’ll also need to modify the wiring harness to allow the H3 ABS sensors to hook up to the Colorado harness. Both trucks used compatible sensors, but different connectors.



With everything bolted up, you just need a wheel alignment, and you’re done. The reward for your hard work? A wider stance up front, along with longer wheel travel and more articulation. It’s a win.
There are other bonuses, too. You’ll also have nicer 12.5-inch brakes up front as opposed to the 11-inch rotors that came stock on the Colorado, and chunkier 33-spline driveshafts as well. With the wheels sitting out farther from the wheel wells, you’ll likely find it easier to fit larger tires (which of course would fit out back, too, since those wheels don’t steer), which will net you some extra ride height. Add in a tweak to the torsion bars, and you might get a little more still!

[Ed Note: I’d be curious about the dynamics-implications of a significantly wider front track than rear. That said, based on what Lewin shows below, it looks like swapping in the H3’s wider rear axle is hardly a huge deal. -DT].Â
Something Different
The front suspension isn’t all the H3 had to give. As noted by off-road shop Badland Industries, you can do a lot more if you’ve got the time and money.
Perhaps most compelling was the fact that the Hummer H3 shipped with particularly interesting differential ratios. Inline-five models came with 4.56 gears, perfect for torquey, low-speed driving off-road. This is a big step up from the 3.73 gears commonly fitted to first-generation Colorado and Canyon models, and some even came with rudimentary locking differentials to boot!
Badland Industries provides a guide on how to swap a H3 rear axle into a first-generation Colorado.


Swapping out the rear axle in the Colorado for an H3 unit doesn’t just provide a better drive ratio for off-road use, it also comes with disc brakes, which are a nice upgrade over the standard rear drums. It’s also particularly desirable if you’ve done the front suspension swap, because it will make sure the rear matches the wider track width up front.
The swap does take some work beyond just bolting in the replacement axle. It can be necessary to tweak the exhaust routing to clear the H3 sway bar links, and you might find yourself having to weld up some sway bar mounts. It’s also typical to need a longer differential breather line to mount to the Colorado’s clips since the H3’s breather is located on the opposite side. You’ll also need to swap specific H3 e-brake cables to ensure the e-brake works correctly.
Swapping out the front diff takes some extra work but can be executed while swapping the front suspension.Â
Of course, if you’re changing your rear axle ratio, you’ll want to change the front to match. Thankfully, that’s readily possible as well, with the cast iron housing making the H3 front differential particularly attractive to modders.
The H3 front differential is unfortunately not a straight bolt-in swap. Forum posters note that it requires using a Colorado intermediate shaft extension tube with the H3 differential assembly to ensure everything assembles properly. It’s also sometimes necessary to clearance some parts to let the H3 diff fit under the Colorado front end, but it’s fairly minor according to forum posts on the matter.


Satisfying
The H3 swap is one of those glorious low-buck junkyard upgrades. If you’re savvy with the forums or have a great local junkyard, you can get most or all of what you need at cut prices. The rest you can purchase as off-the-shelf replacement parts since the majority of what you need is all OEM standard stuff. Shop around and you can pull this swap off for somewhere in the low four-figure range, alignment included.
There’s something compelling about swaps like these. Aftermarket parts are all well and good, but they seldom come cheap. OEM swaps like these can feel like you’re getting great performance for a steal, because you’re smart enough to figure out what bolts up with what. In any case, if you’ve got an old GMC Canyon or Chevy Colorado that needs to be just a little bit cooler and more capable, the H3 swap might be exactly what you’re looking for.
Image credits: Badland Industries via YouTube screenshot, Wrench & Chill via YouTube screenshot, GM
I appreciate these sorts of upgrades, but end of day it’s still a Colorado, the most mediocre truck of its day.
The one bright spot was the 5.3L version, but I don’t know if that was available with 4wd.
it was.
bonus, the the 09 LH8 is all aluminum, makes 300HP and is VVT free. 2010 introduced the VVT, but not AFM thankfully in the LH9 but it makes them a bit less desirable. Also I imagine if you are looking for a solid donor Hummer, look for the Squiggly line button above the radio. if it has this locker button, 2008 and up, then it also has the rest of the adventure package which means a 4 to 1 Transfer case. It is still a Mercedes type full time FWD set up and I am not sure it can be adapted to the on demand stuff in the colorado, but itis certainly a strong ratio for offroading.
I miss these types of upgrades.
My ’96 V8 T-bird shipped from factory with rear drum brakes. A few years after I bought it used I swapped in a complete rear disc brake spindle assy from a wrecked Cougar and a new proportioning valve. Night and day difference.
I did the ’96 front brake upgrade to my ’94 5 Speed SHO. Larger ’96 and up rotors and new (junkyard) caliber brackets for more fade resistance.
My ’89 XJ was a ship of Thessus when I sold it.
As a fan of Subarus, I love the DIY element of swapping parts from other models. You want your WRX/Impreza to have a jacked up rally stance? Put Forester struts on it. They bolt up, and are easy and cheap to find.
Conversely, putting WRX struts on a Forester make for some low street cruising.
The rear sway bar from an STI can tighten up the other models nicely.
Steering racks are also swappable, as long as you have the right combo of hardlines.
There’s even an upgrade for the brakes that uses a Cadillac CTS-V assembly for “big” brakes.
Subaru’s are just large legos.
Fox and Panther bodies are as well. I’m finding parts swaps for Toyota currently.
Ooooh, may favorite Toyota swaps were back when I had a 1st gen Celica in the early 00’s. Since Toyota used pretty much the same stuff suspension-wise from the 70’s until about 1985, there were so many cool Supra goodies, and the wheels swapped, of course.
I love some of the lesser known Fox body cars that can be made into unique (and quick) drivers by swapping the ubiquitous Mustang go-fast parts in. My favorite may be the Lincoln Mark VII.
It’s something we never grow out of. 😉
XJ’s being legos is half the reason I have one, the other half is nostalgia.
Mine’s got WJ front discs, ZJ rear discs, WJ front seats with TJ 2 door tilt hinges, ZJ transfer case and gas tank skids, a minivan overhead console body, 2nd gen Durango diff cover for the 8.25 rear axle, Ford fuel injectors, and there’s plenty of other parts swaps I haven’t done.
That’s not including the 4wd swap I did with native XJ parts.
I love this – I had an ’06 F-150 STX that I discovered could be easily upgraded with parts from more expensive trims, as the wiring harness was already installed, sometimes just needed to add a fuse to the panel. I put on the side mirrors with the LED turn signals, and bam, they worked.
Now I’ve got a ’15 Nissan Frontier, and found you can add the front brakes from the ’10-’12 V8 Pathfinder and get a cheap OEM big brake kit.
Things like this just tickle my fancy.
I love drop in upgrades for cars. It’s like when I found out I could have automatic headlights in my car by swapping out the switch. I have automatic climate control, so the sensor is there, and in less than a minute, I had a convenient upgrade. This is obviously more work but still really neat.
Holy Grail: find a rare 5.3 Colorado and do this swap
or just buy a v8 h3t.
that is even more of a holy grail.
How many H3s do we think are left sitting in junk yards with usable parts? Between the relatively low quantity of them that were made, age, and mid-late 00’s GM quality, there can’t be too many.
Not a lot, as the H3 wasn’t a huge seller. I’m no longer an active participant in the GMT355/360 community, but a decade ago people were offering finders fees if people could find a complete H3 in a junkyard because they were so tough to come by. I can’t imagine time has improved that, especially since H3s have become sought after and therefore less likely to end up being scrapped.
I may have missed something but the piece says most of this stuff is off the shelf which I took as you can buy them at a parts store.
I suspect most of this can be bought new and shipped to your garage.
I bet that isn’t very cheap, and you’ll probably find some critical part is no longer made as the H3 was low volume.
It is usually more of an issue with the Alpha V8 models since they had an iron front diff versus aluminum, and many of the engine parts are somewhat bespoke to fit int he engine bay.
I will say however, you can sometimes find most of this stuff for dirt cheap on Rockcrawler classified ad space. Straight axle swaps and Atlas T-Case upgrades on the few Alphas still out there is a real thing, just a pain to only partially do because of the Yaw controls and steering sensors interconnected with the ABS system.
I think this is actually a really good idea.
I’d swap in the T-case from an H3, since it’s basically a later iteration of the (underrated) NP242 case, but goes by a different name.
I’d also swap in the iron front diff, but going with wider track for the front, I think i’d skip that.
Too bad these trucks suffer from the dumb front axle spline issue, along with Trailblazers, Envoys, etc..
I very much dislike that wide-track look on pickups. Especially when someone doesn’t have fender extensions/mudflaps.
Every time I see one in traffic I tell whoever else is in the car that it looks like a roller skate.
“Mah truk haz girth”
I’ve seen a huge swell of poked, small wheels and Carolina squat on the same truck. I wonder if people do the mods one at a time and think “Yeah, it’s obviously worse just like I expected, but I think I could make it several times worse if we just do all the work at once.”
Every time I see one of these modified trucks/jeeps, have flashbacks to my high school days in a smaller southern town. The police back then had nothing else to do except harass high school kids and their vehicles. They would have had you for multiple equipment violations such as no fender extensions/mudflaps, bumpers too high, too dark window tint, loud exhaust, etc, etc.
Now the population has quadrupled, so they now have drugs/gangs to keep them busy.
I recall the local yocals pulling us over for partially obscured front license plates if you had a bra on your car. these days they just let the cars with 3 year old temp tags drive right on past.
Side note, the bolt pattern is the exact same as Nissan 6 lug smaller trucks. So you can at least get up tot he more standard 17 inch wheel sized used offroad these days.