Jeep Wranglers are rugged four-wheel-drive vehicles. That’s what they were born to be, and since the beginning, they’ve been executing that mission flawlessly. You would think that if you bought a manual Jeep, you could rely on the transmission to just work, given that Jeeps have had floor-mounted stickshifts for over eight decades. The last few years have revealed that’s anything but the case. Recall after recall goes by, but owners are still crying out for help with trucks that simply don’t work.
The problem concerns Aisin AL6 six-speed manual-equipped Jeep Wrangler JLs from model years 2018 to 2023, as well as Jeep Gladiator JTs from years from 2020 to 2023. These vehicles feature a clutch pressure plate that can overheat due to friction. In extreme cases, the pressure plate has been known to fracture. This can be an extreme event that sends hot shards of metal blasting through the transmission case which can set fire to the vehicle. Though it’s a rarity, it’s actually happened out in the wild.
Jeep has been trying to solve this problem for some time. Manual transmissions are simple and well-understood, so you’d think this would have been sorted quickly. The Autopian spoke to Jeep customers struggling with this very problem, though, and the reality isn’t so grand. Some have turned to aftermarket repairs, while others are tangling with multiple recalls and constant error codes with no end in sight.
Source Of The Pain
The clutch assembly is a critical element of any manual transmission vehicle. The clutch is responsible for transferring power from the engine to the transmission. Any fault with the clutch assembly can make a vehicle nigh impossible to drive, and this could be dangerous in some scenarios. In the case of the Jeep Wrangler and Gladiator, the problem initially lay with the pressure plate. But what is a pressure plate?
A pressure plate is bolted to the main part of your engine’s rotating assembly, the flywheel. The actual clutch disc sits between the flywheel and pressure plate, and is connected to the transmission input shaft via a spline. The pressure plate’s job is to clamp the clutch to the flywheel. This makes the engine and the transmission input shaft all rotate together, thus connecting the “wheels” to the engine, moving the vehicle forward. When the clutch pedal is depressed, the pressure plate falls back and releases the clutch; the clutch disc is no longer clamped between the pressure plate and flywheel, and thus the engine is disconnected from the transmission (and thus the wheels).
As per recall documents filed with NHTSA, Jeep’s manual transmissions were overheating the pressure plate. The problem was so bad that the pressure plate could fracture, potentially so badly that hot fragments could escape the transmission case and even start a fire.
Issues Begin
It took a few years before Jeep realized the scope of the problem. But the clues were there from day 1. Go back to the very first drive review from Motor Trend in 2018, and they’d tell you the manual wasn’t a great experience. “The clutch take up on the six-speed manual transmission is so vague even our officemates at JP and 4-Wheel and Off-Road were stalling,” said Scott Evans. Car and Driver was similarly unimpressed. ” Further, the clutch engaged with an abruptness that saw many experienced drivers stall the thing,” wrote Daniel Pund.
Jeep Reduces Engine Torque To Try To Solve The Issue
According to documents filed with NHTSA, Jeep first became aware of the issue in 2020. Investigations began after a 2021 model year Jeep Gladiator suffered a fire at the company’s Toledo North Assembly Complex. More cases filed in over the following months, and Jeep eventually issued a recall, with a software update believed to be the solution to the problem.
In some circumstances, the clutch pressure plate may become overheated
through friction, which may lead the pressure plate to rapidly fracture. When a
pressure plate fractures, it may result in cracks or holes in the transmission
case, allowing heated debris to be expelled from the transmission case.There is no defective part. The issue is the result of design specification.
Remedy is updated software for the vehicle that mitigates safety risks
related to the clutch assembly.
-NHTSA Part 573 Safety Recall Report, 2021
The software update would reduce engine torque in the event the vehicle’s computers detected potentially elevated clutch assembly temperatures. The Jeep transmission doesn’t have any way to directly measure the temperature of the clutch, however. Instead, Jeep engineers figured out that they would estimate clutch temperatures indirectly. The clutch assembly generally gets hot when the clutch isn’t fully engaged, and is allowed to slip relative to the flywheel and pressure plate. The sliding friction generates a lot of heat, which can damage components. By comparing engine RPM with vehicle speed sensor signals and the current gear selection, it’s possible for the Jeep’s computers to determine whether or not the clutch is slipping, and thus is likely to be getting hot.
Jeep rolled out this update under a recall campaign beginning in 2021. Eventually, it became obvious that this update wasn’t solving the problem. Jeep realized that vehicles built after the initial recall were still suffering failures in the clutch assembly.
By early 2023, Jeep was issuing another recall and a stop-sale order for the same problem as warranty complaints stacked up. The new recall involved the replacement of the clutch assembly along with further software updates to the Instrument Cluster Module (ICM) and Powertrain Control Module (PCM). The hope was that this would eliminate the overheating issue and ensuing failures.
James’s Trial
I recently spoke to James Wamsley, whose truck has been afflicted with this very curse. He bought a 2023 Jeep Gladiator Mojave with the manual transmission. He was stuck waiting for delivery while Jeep sorted out the transmission issues, as the recall effort had included a stop-sale order. He eventually scored his new truck in December, having been told the recall work had been handled.
Fast forward a few months, and he was out in his new truck on an adventure in the Outer Banks of North Carolina. “Since this was the first outing of the new truck, I chose a firm beach,” he explains. “After shifting into 4 high, I basically let the clutch out once and cruised along.” As an experienced driver, he didn’t foresee what would happen next. “First I got a warning that auto start-stop was disabled, then a high trans temp warning, then a Service Transmission warning, all within a half mile of hitting the beach.” He hoped that letting the vehicle cool down would be enough to reset things, but it wasn’t to be. The vehicle remained in a limp mode, with severely limited torque. “It pretty much renders the vehicle undrivable,” he says.
Upon getting the vehicle to a local dealer, he was questioned if the problem was user error. ” I assured him that I’ve been driving on the beach with manual transmissions since 1992, and this is the first problem I’ve encountered,” says James. The dealer performed a reset on the vehicle and sent James on his way. “The next day I tried using 4-Low instead of 4-High, thinking maybe the bogging down heats the clutch,” he explains. Alas, the problem reoccurred again in just half a mile of sand driving.
He had the local dealer reset the vehicle once more so he could get home to Pennsylvania. He’s been pursuing a proper fix since then, but to no avail. “The local dealer can’t replicate the issue, because there’s no beach in Pennsylvania,” says James. “After two service visits and three weeks in the shop, they’ve fixed nothing, and say the vehicle is operating normally.”
A VIN check by The Autopian confirmed that his Gladiator had the work performed for recall 19A. And yet, James is stuck with a truck that keeps throwing errors. He can no longer trust his truck off-road. “Jeep is saying there’s no issue, that’s what it’s supposed to do when the clutch gets hot,” he says. “So, again, the whole Desert Rated [badge] comes into question.” It’s a great point, given the Mojave trim is literally named after a sandy wasteland.
He’s heavily pursued the issue with the Jeep Wave customer care service. Eventually, he says Jeep’s Customer Retention Team agreed to a Service Technical Assistance Resource (STAR) case, where the matter is escalated to a higher level of technical investigation within Jeep itself. But even that didn’t get him anywhere. “Currently, the jeep is at the dealer, the dealer said that the STAR case was closed by Jeep with no problem found, so there’s nothing they can do,” he says.
James says his biggest disappointment is with the way the company has handled his case so far. “They are simply stating there is no issue because it’s operating properly,” he says. “It’s like saying, your boat sinks when you use it, but when you bring it back for service, it’s on a trailer, so we can’t make it sink.”
At this time, there still aren’t parts available for many affected vehicles. That includes some on the used market, too, which still have recalls outstanding. Documents filed with the NHTSA in March 2024 indicate that recall parts are still not available for Jeep Wranglers or Jeep Gladiators built for the 2020 to 2022 model years.
A 1,100-member strong Facebook group titled “Jeep clutch recall” has been spawned on the topic, with owners sharing stories of successful fixes and ongoing woes. Some have had the recall work completed without issue, while others have continued to suffer problems. Just like James’s story above, they report that the Service Transmission warning recurs regularly even after the recall. Some owners are regularly using scan tools like JScan or Tazer to reset the warnings when they appear.
Others have thrown their hands up and sought external help. Many in the group have had aftermarket clutch kits installed as a solution to the issue. Some have had success getting Jeep to reimburse them for replacements handled by outside workshops, others have not been so lucky. Given that a clutch replacement can typically cost from $2500 to $4000 on these vehicles, it’s easy to see why some customers are eager to have Jeep pay to solve the problem.
I spoke to Todd Spencer, the proud owner of a Jeep Wrangler with a manual transmission. He went the aftermarket route, rather than waiting for Jeep to supply parts. “I installed a Centerforce 2 Performance clutch and flywheel kit with all the upgraded hydraulic cylinders… It’s the fix for the Jeeps,” he explained, noting he received a $3,100 reimbursement from Jeep for the swap.
“It’s like a night and day difference,” Todd says. “It engages as a clutch should now, and holds!” He’s running a 3.5-inch lift and 35-inch tires, and he’s had no fault codes.
The aftermarket parts aren’t a silver bullet for everyone, though. Some forum users have reported that they’re still seeing Service Transmission warnings come up at times, even with a new clutch fitted. Aftermarket Scan tools like JScan and Tazer have been implementing reset features to clear the lights for owners that are seeing the message reoccur regularly.
I decided to hit up Z Automotive, the company behind the Tazer flash tool. Company president Joe Zizzadoro got back to me, explaining that he’s bought a 2020 Jeep Wrangler specifically to investigate this issue and try and develop a remedy. He was able to provide excellent insight into the matter.
The clutch recall flash that is out at the moment affects 2018,2019, 2023 and 2024 Jeeps only. They haven’t put out the update for 20-2022 as of yet, and they probably shouldn’t!The PCM flash includes code that estimates clutch temperature based on engine RPM vs wheel speed. They seem to use a combination of hardcoded math and some variables that a re measured after a reset that are stored in the PCM’s EEPROM.If stock tires and gears are used, there seems to be no problem. The issue is that once the tire and/or gear ratio calibration is changed, the PCM doesn’t use these new values to re-calculate the clutch temps. This will cause the hot clutch messages and reduced engine power.
A Working Theory
After talking to James, Todd, and Joe, I’ve got a working theory on what’s going on. Taking a look at Todd’s flywheel will tell you one thing—the original clutch assembly as delivered on his 2018 Wrangler was definitely overheating. He’s replaced that clutch assembly with an aftermarket one, and he’s happy. The problem is fixed, as far as he’s concerned.
The same can’t be said for James. His Jeep Gladiator has had the 19A recall done. That means it has a new clutch assembly fitted, and it’s had the computers flashed with Jeep’s updated software, too. Now, it’s possible this clutch assembly is still defective, and it’s slipping and overheating. That’s certainly what his Jeep is telling him when he drives on sand.
However, there’s another possible explanation for James’s troubles. Could it be that the updated software on the powertrain control module in James’s Gladiator is throwing a fit because it thinks the clutch is slipping when it isn’t? If the new software is overly sensitive to clutch slip, it could be throwing errors when it shouldn’t be. Given Joe’s note about the difficulty of calibrating the PCM properly, there could be something in this.
It must be stated that this is just a theory; it’s not confirmed by Jeep, and we don’t have enough evidence available to confirm it outright. Nor is the following statement advice—it’s just a statement of what I’d do given what we know. If I had a Jeep right now, I’d skip the official recall and software flashes. I’d get an aftermarket clutch put in and have it reimbursed by the automaker. It’s only anecdotal evidence, but Todd’s got a working Jeep, and James hasn’t. I’d follow his example based on what I know right now.
Update from Jeep
The Autopian sought comment from Jeep, particularly regarding the parts availability for the recall. Jeep provided a statement this week regarding the matter.
We have been servicing vehicles since November of last year. Service completions are growing daily. To date, nearly 8,500 customers have responded to their recall notices and we urge all affected customers to do the same. The remedy is being phased in by model-year. We expect to mail the final group of notifications in August.
The automaker confirmed that the current 19A recall involves full replacement of the clutch assembly, as well as reprogramming of the Instrument Panel Cluster and Powertrain Control Module. However, Jeep declined to provide any additional detail on why the clutch had an overheating problem, beyond putting it down to friction.
For owners still facing issues post-recall, the automaker had only this to say. “We urge customers to contact their dealers whenever they have concerns, for any reason,” read the statement. That will come as little comfort to owners like James, who has been around this merry-go-round time and again already.
Some owners on Facebook are now reporting they’ve been told a work stop has been issued for the recall. That would make a lot of sense given the troubles customers are having in the field. The Autopian contacted Jeep for clarification on this point, which stated that “remedy availability is being phased in by model-year. All model-years will be covered by August.”
Supposedly Proven Technology
The simple fact is that the manual transmission has been around for a century at this point. Countless vehicles use them, from the cheapest hatchbacks to the finest sports cars on Earth. Neither the Jeep Wrangler nor the Jeep Gladiator is a particularly special case. Designing a functional manual transmission for these vehicles should have been straightforward work for an established automaker.
Instead, Jeep released a vehicle with a defective clutch assembly that required full replacement. Even more strangely, it didn’t catch the problem until after the first recall applied a software fix to a hardware problem. The fact that the second recall still hasn’t solved things for some owners is yet more concerning.
Customers generally have an expectation that a new vehicle will be fit for purpose. In the event of issues, they expect an automaker to fix them in a reasonable period of time. When fixes take years, or multiple fixes fail to solve the problem, they quickly lose faith in a product. It’s no surprise that many are considering legal options to solve their problems where Jeep has failed.
James is being forced into that position himself, but it’s not the way he wants to go. “The truck is technically my wife’s, and she cries about it,” he says. “She doesn’t want to lemon law or try for a buyback… she just wants it fixed.”
The Autopian has reached out to Jeep for more information on the matter. Namely, our questions are the same as many customers out there. What is the root cause of this overheating problem, and what are customers to do when their car still throws error messages after a recall repair?
There’s a bigger question, though, that we probably won’t get a real answer to. In 2024, how does this happen in the first place?
Image credits: Jeep, James Wamsley, Facebook screenshot, Todd Spencer, Clutch Industries via YouTube Screenshot
I worked on the JL and JT at launch. The manual transmission in those things is a travesty – The JK NSG370 was such a joy to drive with a good clutch pedal feel and a great direct acting shifter. The people who complained about it seem to be confused about the fact that the shifter throw and speed of a Jeep or other truck like vehicle shouldn’t be the same as a sports car.
The JL transmission, in contrast, has a terrible cable shifter, horrible compound bow style clutch pedal assist, and terrible ratios that make the thing fall on its face shifting into 4th. I could visibly see the firewall flex from pushing in the clutch.
I drove manual JKs in the company fleet as much as I could. When I lost my last JKs, well, I just didn’t drive manual Wranglers any more.
2022 manual rubicon gladiator owner here to share some additional thoughts.
It’s interesting to me how this has all played out. I pirchased mine last June with just under 10k miles used, knowing there was a stop sale but still wanting a manual.
The truck is indeed a PITA to drive, the clutch is very spongy with very little feedback and has an almost light switch engagement. Its horrible to drive in stop and go traffic or drive thrus, let alone teach my girlfriend how to drive it.
I’ve been to 2 different dealerships over the past year to inquire about parts availability to get the recall done, and each time (most recent was about a month ago) only to learn this last time that the “fix” for the 2021 and 2022 vehicles literally does not exist yet. Maybe they were blowing smoke up my ass who knows, but they said the 21 and 22 have slight differences due to this fiasco that mean the current updated clutch will not fit those vehicles. And there is no eta date for literally any of that.
Meanwhile, i have said to hell with it if the clutch goes its not my problem and have towed and done some serious off roading for what the truck can do in its stock form and have not had issues. Even when riding the clutch to the point of actually getting some clutch smell (blame that on low speed off road stop and go uphill) and have never once seen that message. That only happened once however. The clutch does slip a tiny amount on occasion, has done that since new and has not become a worsening problem.
Outside of as previoisly referenced it being a PITA transmission to live with on a daily basis, I have not had major issues. But jeeps lack of response and clarity about this has been very disapppointing to say the least. I doubt we’ll ever truely see the end of this fiasco. The 6 speed is absolute garbage and imo they shoild have kept the 6 speed from the jk or just dropped it altogether.
I remember being excited about Jeep going back to an Aisin transmission given my experiences with the one in my 13 JK. Now it looks like I’d avoid any JL with a manual on the used market. Jeeps reliability and prices these days are a joke.
I had a 19 JL with a manual and since it was a lease and buyback value was high I swapped it for a 22 automatic because that way I could get the cold weather package with remote start. I’ve driven manuals for years but that clutch was so grabby I couldn’t stand it. Broke my heart to go back to an automatic but living in MN the remote start package is darn near a must for me. Is the grabby clutch just the way truck clutches are supposed to be since they handle more torque? Is this a symptom of the underlying design problem Lewin is writing about? If I could get a clutch that wasn’t miserable and an aftermarket remote start I’d get another model in a heartbeat.
Reading that there is a heavy clutch-pedal assist spring on the pedal, I wonder if removing that spring or at least replacing it with a softer one (a very common problem/fix in the BRZ/86 community) can mitigate some of the clutch touchiness? The spring is there to make the clutch pedal easier to push to the floor, but it tends to cause the pedal to sort of snap back at the worst possible moment when re-engaging the clutch. The most common victims/complainers about these springs are people who have driven manuals their whole lives.
Jeep is hoping the experience and pain of others will convince as many people as possible to buy the automatic. Manufacturers are trying as hard as they can to eliminate the option of manual transmissions as it costs them twice as much to certify two different drivetrains. This is probably planned and calculated.
I’m the new owner of a ’18 JLU with the 6 Spd. it had 59K on it when i picked it up in April, and it’s been mercifully working as intended so far. i fully knew about the recalls before buying it, and intend to replace the clutch with a CF unit if/when the original has issues. i really like the vehicle as a whole, though you’re absolutely spot on about the vague clutch bite point. it’s been a bit of a challenge to get used to coming from my Fiat Abarth.
I’m hoping I’ll be mostly fine because i don’t plan on any advanced off-roading, mostly fire roads and gravel stuff. maybe something as easy as Schafer Trail in Moab while I’m out there mountain biking.
i bought more than i really needed for that sort of stuff, mainly because i wanted a 4WD vehicle that could seat 5 and was some sort of convertible, but i wanted to be able to get to places for camping that an AWD BMW or some such couldn’t get to or have storage for my gear.
My son and daughter each have a JK w/ the 6 speed. She has about 175k on hers and the original clutch. OTOH, it does occasionally pop out of 1st & 3rd gear when leaving a light.
There’s a part of me completely surprised that corporate hasn’t said Wait, you took the vehicle off of a paved roadway? Warranty voided. Have a nice day!”
I mentioned to my wife several years ago that I was concerned auto manufacturers would forget how to design and specify manual transmissions.
I figured we’d start seeing higher numbers of manual transmission issues caused by more resources put to the complex automatics, the retiring of the experienced workforce, and the assumed “simplicity” of manuals.
It had to start somewhere – it sucks that it started with Jeeps that have such a high manual take rate.