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2015 JGC 8-Speed Transmission Issues

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2015
19K views 38 replies 14 participants last post by  Eugene The Jeep 
#1 ·
Hi all,

Just curious if anyone else here with either a 2014 or 2015 JGC had or is currently having issues with 8-speed trans? I just can't get used to this thing. It never drives the same way twice. I know that the dealer won't be able to reproduce or ID any issues; it is just a quirky ride. Am I alone in this? Sometimes the upshifts from 1-2 or 2-3 feel late, other times, it glides without issue. Once I make it to 3 and up, it's smooth sailing. The main gripe is getting there. I find it most noticeable at first upshift after having been parked. Seemed to be more prominent with ECO on at first, but even had a couple instances of "quirkiness" with ECO off. A call into the dealership yielded the response "The 8-speed requires getting used to." I also feel that when you are in ECO and the thing wants to upshift and you decelerate for whatever reason, it'll keep RPMs high so it can still upshift on its own. I know the ECO mode changes the "shift" schedule, so I assume this is all part of that. By the way, car is 1 month old, 1000 miles. 2015 Limited. Thanks for reading!
 
#3 ·
If you do a search you'll see you are far from the first to post about this. If you read the other threads you will learn more about the issues and which 8 speeds are more likely to be affected.


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#5 · (Edited)
I just took it for a spin with ECO off. Its a lot better now. So hard to tell what affects this. I know adaptives play a role. Perhaps if I drive it awhile with ECO off, the software will have enough historical data to do the right thing. I've been turning ECO hoping that it'll be better without it, but when it's not different one minute in, I turn Eco back on. so maybe I'm
Not giving non-Eco a chance. Even if I'm wrong, don't tell
Me. Don't burst this momentary bubble of optimism
 
#6 ·
I have a 2015 gas 6 and we have had no problems with the trans. My wife mainly drives it and she's easy on the throttle. It's a learning transmission, so I guess it's adapted to her style. The only minor issue that i notice is that if you stop quickly from a high speed, the transmission has trouble keeping up with the downshifts at the end and there can be some a a couple of rough shifts at the very end, almost like a stutter in the drivetrain. I think that's due to the 8 speeds. But it's not a big deal. The low range shifts tend to hang at a cold start, but once we have driven a mile or so and the drive train starts to warm up, the shifts are fine for me. We have driven the Overland for 7 months including a trip from DC to C/FL. So far no repairs needed. Mileage is a little lower than I had hoped, but now that we're up to about 6k miles, I'm hoping for better mileage. Other than that, it's been trouble free.
 
#9 ·
I'd wait a few thousand miles more. Although my new 2015 seemed to feel perfect from day one.


My 2014 which had several firmware updates and what felt like a long break in to feel right. Part of that break in, might have been ME. After that it was silky smooth 0mph to what ever and back to 0mph. Never bother shutting off ECO mode.


The problem could be a valve body issue, which seem to be hard to diagnose with all the other issues floating around including the learning phase (for both user and transmission).


The problem could be partly you. It drives great for me. But it may not be your cup of tea if you drive differently.


It never seems to shift too late or to early. And does not hunt on the highway hills.
It's just rock solid. It never hesitates when you step on it, from a stop or on the highway.


If it is hardware, hopefully it will get bad enough soon to be obvious for the dealer to fix.
 
#11 ·
I noticed a similar issue in my 2015 Overland, quirky is the word I would use to describe it as well. In particular, I had the "lag" between 2nd and 3rd gear. Almost like an old fashioned turbo lag. Nothing huge, just an annoyance that made me worry a bit that it was a symptom of bigger issues. Changing back and forth from Eco would sometimes seem to help and other times would not. Changing to "sport" always helped because the V8 makes me grin:D

I am at 2000 miles now and things seem to be evening out. The transmission is learning about me and I am learning about it. I am leaving this week on a 3-4000 mile trip so I'll see how it feels after that.

Not a single other question about the truck. No worries, no squeaks and rattles, nothing.
 
#15 ·
Well this forum sure is lucky to have you to decide which problems are "legit" and which are "inane". Looking at your responses, it seems that they are all judged to me inane. Just my opinion.
 
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#22 ·
I don't think my sport mode even functions properly. All that it seems to do is hold the gear for an unusually long period of time. So RPMs will be high, but there isn't an upshift where and when you'd expect it. Just love that my $42k car drives like its being operated by someone learning stick shift for the first time.


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#24 · (Edited)
I don't think my sport mode even functions properly. All that it seems to do is hold the gear for an unusually long period of time. So RPMs will be high, but there isn't an upshift where and when you'd expect it. Just love that my $42k car drives like its being operated by someone learning stick shift for the first time.
Well that is what Sport mode does, so it sounds like its working. By holding higher revs it is accessing more power. It also reduces traction control, and pushes more power to the rear wheels.

The torque converter introduces a bit of lag, particularly at take off, and particularly when its cold. It just takes a while to bind up when its cold.

I haven't met a perfect auto trans that shifts when I would expect it to shift. Its always more noticable at low speeds when you are trying to build momentum, more so than at higher speeds when momentum is already there. My old landcruiser would always pick the wrong gear at a certain speed on a certain corner just down from my house. Drove me nuts.

Interesting that your wifes car doesn't have the same characteristics as your car. I guess it could be the learning, you could ask the dealer to reset it to relearn.

There's a bit of info in this TSB:
http://www.wk2jeeps.com/tsb/tsb_wk2_2101214b.pdf
 
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#32 ·
I know this is a controversial topic on this forum, so I'm really sorry if I drew anyone's ire. My Jeep is at the shop now. Let's see what happens.

My chief complaint was delayed upshift, 1-2 and 2-3, most noticeable after car has been parked and most severe in am.

The secondary problem is a very noticeable "drag down" feeling when the car downshifts in deceleration. There is a "pull" from 5-4, 4-3, etc.

As I told the service manager, if this is the way it is, then this is the way it is. I just want to make sure there isn't something more at play here.

Again, I am spoiled by my wife's 2015. He car literally "glides" through the shifting, both up and down. And there is no dragging, lagging, etc.

According to the service manager, my disconnecting the battery did delete the transmission data, but what is does not do is reprogram the "relearn" routine. I guess that means it defaults to factory parameters.
Who knows? However, when I did have it flashed with the relearn five weeks ago, the great results were short lived.

I'm resigned to change the way I think about my car. Perhaps I need to stop expecting to "enjoy the ride" and just expect it to get me from A to B and back again.




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#33 ·
Again, I am spoiled by my wife's 2015. He car literally "glides" through the shifting, both up and down. And there is no dragging, lagging, etc.

According to the service manager, my disconnecting the battery did delete the transmission data, but what is does not do is reprogram the "relearn" routine. I guess that means it defaults to factory parameters.
Who knows? However, when I did have it flashed with the relearn five weeks ago, the great results were short lived.
Well you have the benefit there of being able to compare 2 cars (I'm guessing they are similar build dates too?). So your experience is somewhat objective. It's a bit difficult for the service guys to argue 'that's just how it is' when you have another car that is behaving differently. Keep on their case, as I said before, the re-learn procedure is a bit complicated, if they don't do it right it won't store the correct change parameters. Perhaps they need to do it again. Either way, I'd keep on them about it, it sounds like there is a problem somewhere.

I get lag in the morning, when the car is relatively cold. But its mainly from stop into 1st. The torque conveter seems to take longer to engage. Once its warm its all smooth. Rest of my shifts are smooth. But I have a diesel, so the trans is a different version to yours.
 
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#35 ·
Heard back from service. They were able to duplicate the problem, so I have that going for me. As for a fix? They opened up a case with Chrysler Engineering and are waiting to hear back. The saga continues...


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That's half the battle good luck.

Keep in mind that the transmission does some downshift braking.

As soon as you touch the brake it may downshift and use the engine to help slow the vehicle.
 
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