Spend enough time driving a manual transmission, and odds are you’ll eventually slip your car’s shifter into the wrong gear. Most of the time you’ll catch it, but if you don’t, and downshift when you meant to upshift, you can risk “money-shifting” your car. Inadvertently going from a higher gear to a lower gear while accelerating can, at worst, cause catastrophic damage to your engine as it over-revs to keep up with the wheels. It’s called money-shifting because the shift causes damage expensive enough to empty your bank account.
If you’re lucky, and your engine can handle the revs, you might just get away with a tire-chirp as the engine slows down the rest of the drivetrain to match revolutions. I’m not ashamed to admit this has happened a couple of times in my driving career, and I’ve learned from it.
Automatic transmissions usually don’t have this problem, since they have computer logic that shuffles the gears in sequence as the car accelerates and decelerates. But what if that software goes haywire? Well, a bunch of Ford F-150 owners have apparently found out first-hand.
Following an investigation launched in February, Ford is recalling nearly 1.4 million F-150s built in the mid-2010s over worn-out electrical connections in the transmission’s computer system, which could send incorrect signals to the gearbox, ordering it to suddenly shift from sixth gear all the way down to second gear without warning. It’s like a money shift that you have absolutely no control over.
The recall, published to the NHTSA’s site this morning, targets 1,392,935 F-150 pickups built between 2014 and 2017 and equipped with the six-speed 6R80 automatic transmission. Specifically, the problem lies with the Transmission Range Sensor (TRS), which tells the car’s ECU which gear the transmission is in. This is part of the transmission lead frame, a molded plastic piece mounted to the gearbox that’s sort of like a circuit board for the transmission, connecting all of the valve bodies to the solenoids.
According to Ford, it’s this lead frame piece that causes the problem. From the recall document:
Degradation of the electrical connections in the transmission lead frame due to thermal cycling and vibration can result in a momentary detection of incorrect TRS signal positions by the PCM. A faulty TRS signal can lead to an unintended downshift.
Basically, the faulty sensor is giving the wrong data to the ECU, communicating incorrect positions that make the transmission think it should be in second gear, not sixth. This is pretty scary, because usually you’re only in sixth gear when you’re already moving at highway speeds. And as anyone who’s nearly money-shifted a car knows, dropping your car into second gear while moving at high speeds is a bad time.
Like I mentioned before, in addition to over-revving the engine, shifting from sixth to second forces the wheels to match the engine’s speed (which is suddenly much higher due to the 6-to-2 downshift). This is where things can get really sketchy, especially if you’re moving quickly. From the recall doc:
An unexpected downshift to a lower gear may cause an abrupt wheel speed reduction for a short duration, which in some situations could cause the rear tires to slide until the vehicle speed slows. This condition could result in loss of vehicle control, increasing the risk of a crash.
Ford predicts that only 1% of the nearly 1.4 million potentially affected trucks actually have a problem with their lead frames (around 14,000 vehicles). The company says that in the U.S. alone, it’s received 444 warranty claims, 121 field reports, 105 customer service reports, and 316 complaints through the NHTSA. Despite the scariness of the fault, only two injuries and one crash are potentially related.
Interestingly, this isn’t the first time Ford has had to deal with this problem. Back in 2019, it recalled a bunch of 2013 model-year F-150s with the same transmission for a similar sudden downshifting problem.
The fix is pretty simple. Anyone with an affected F-150 can take their truck to a dealer to have the software updated. Ford says the updated software includes “additional time for the control system to recognize failed or failing TRS hardware prior to commanding the downshift during this unique shift command fault.”
And if your truck comes into the shop showing signs of a failing lead frame, like trouble codes from the ECU, Ford says it’ll simply replace that part altogether, along with the new software.
My advice? Even if your F-150 is running perfectly, just get the damn recall done. This is one of those things that, if not addressed, could cause huge damage to your car and even yourself if you end up in a crash. I wouldn’t want to know what a 6-to-2 downshift feels like if I were piloting something as big as an F-150 at highway speeds, much less while potentially towing a huge trailer.
Top graphic image: Ford
In the seventies I drove rental cars at LAX. Some drivers would shift ford and Chrysler products into reverse at speed, causing the rear end to lock up and slide. GM products would “override” the shift and go to neutral. In two years only saw one blown engine.
This will be on everyones to do list, right behind the Takata airbag replacement.
First gear, it’s all right. Second gear, hang on tight.