Surging

[Jessie_Trudeau]

I’m having some symptoms in my 2020 Jt 2400 miles in it . Light throttle or steady state cruise, getting a bucking / surge / bogging / pumping brake feeling. It could also be described as a straight strong head wind pushing on the front of the Jeep. The easiest way to tell for me is, 1-2* incline ( used off road pages for that info ) try and stay around 25 mph steady. It can't do it. Feels like someone is pumping the gas, or brake pedal. I have tried manual mode, no change. It does the same at rpms from 1300-4000 rpm.Any gear,did not try any higher rpm. Once you know what your feeling, its at any speed ( mph ) or gear. The only thing that seems to be consistent is the rpm 1300-4000 rpm, with light or steady speed.
I have an appointment soon. Hope they have live data stream to find out what's going on.

Anyone else feeling this?

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[JohnFinx]

I feel something like that sometimes, like I just drove through bouncy jello.
The other day my transmission was unable to decide what gear it was in, at 45 mph it went shift up-down-up-down about 15 times while in 7th (the indicator did not change). When slowing down it lunges forward when it downshifts from 5 to 4.
I'm taking it in today, and I can guarantee 100% the problem will disappear on the way there.
7500 miles.

 

[Jessie_Trudeau]

I feel something like that sometimes, like I just drove through bouncy jello.
The other day my transmission was unable to decide what gear it was in, at 45 mph it went shift up-down-up-down about 15 times while in 7th (the indicator did not change). When slowing down it lunges forward when it downshifts from 5 to 4.
I'm taking it in today, and I can guarantee 100% the problem will disappear on the way there.
7500 miles.

I bet same thing here

 

[DAVECS1]

Are both these jeeps stock? I am just curious as I have been doing some work on the calibration for the supercharger setup that goes on the Gladiator, and sae this same behavior. The fix was a table for the throttle body control that should not have needed touched from stock or at least that was is my opinion. This would would lend some credence to my thought if these are stock.

 

[Jessie_Trudeau]

Are both these jeeps stock? I am just curious as I have been doing some work on the calibration for the supercharger setup that goes on the Gladiator, and sae this same behavior. The fix was a table for the throttle body control that should not have needed touched from stock or at least that was is my opinion. This would would lend some credence to my thought if these are stock.

Mine is stock as can be rubicon

 

[JWGladiator]

I have the same issue plus a clunk going from 5th to 4th. Took it in to the dealership 2 weeks ago and the behaviour decided to disappear and they said they couldn't replicate it. They reset the transmission learning and I have driven it another 200 miles with the same issue happening. It generally feels like I am driving with a 16 year old learning a stick shift.

Stock 21 Mojave - ~1,000 miles. Super frustrating.

 

[DAVECS1]

Thank you for the info. In my opinion this is a Chrysler issue. I would not beat up on the dealership too hard. This is programming they do not have access to. I would ask them to make sure your machine has the latest software flashed to it as it may have fixes for this. Most machines should adapt out of it. The stock programming is set to change parameters after approximately 35 miles or so. So drive consistently how you want it for that time and it should get better. Definitely frustrating.

 

[JohnFinx]

Stock Overland. I just returned from the dealer, and this is what they told me (summarizing):
1. It is a "smart" transmission and will shift when IT thinks it should...not when you think so.
2. It "learns" your driving patterns and when you drive differently due to terrain or traffic it may "confuse" the system and it may shift weird. (Perhaps that's what happened to me. Although jerking around like I'm re-entering the atmosphere from a space mission is a terrible "guess" in my opinion.)
3. It may occasionally get a "glitch" as computers are apt to do...but usually fixes itself upon reboot/restart.
4. If it doesn't throw a code, they have no idea what to do about it. Drive it 'til it dies. I guess mechanical issues never happen without the computer knowing about it. (yeah, right...)

So I'm just going to deal with the weirdness, it certainly is not the first vehicle I've driven that I had to adapt to its quirks.

 

[flatboycms]

I have noticed something similar with my 2021 Mojave. My approach is I am disabling traction control every time I get in. I am playing with the idea that this stops the transmission from tracking driving habits or it is tracking them differently due to the traction control. Sometimes it is smooth and no issues other times it is still the same
"wind" effect. Only 600 miles on it so far. I figure I will give it to 3k and see if an how it calibrates itself.

 

[JWGladiator]

Stock Overland. I just returned from the dealer, and this is what they told me (summarizing):
1. It is a "smart" transmission and will shift when IT thinks it should...not when you think so.
2. It "learns" your driving patterns and when you drive differently due to terrain or traffic it may "confuse" the system and it may shift weird. (Perhaps that's what happened to me. Although jerking around like I'm re-entering the atmosphere from a space mission is a terrible "guess" in my opinion.)
3. It may occasionally get a "glitch" as computers are apt to do...but usually fixes itself upon reboot/restart.
4. If it doesn't throw a code, they have no idea what to do about it. Drive it 'til it dies. I guess mechanical issues never happen without the computer knowing about it. (yeah, right...)

So I'm just going to deal with the weirdness, it certainly is not the first vehicle I've driven that I had to adapt to its quirks.

Pretty much verbatim of what I heard from my local dealer. Plus the added " you have a warranty, we will fix it when it breaks." Real comforting. Crossing my fingers that the longer we drive these issues will fade.

 

[cecaa850]

If the vehicle doesn't act up for them, has the latest software and there are no bulletins addressing your specific problem the dealership will have no idea what to do to repair it.

 

[bsd103]

Are both these jeeps stock? I am just curious as I have been doing some work on the calibration for the supercharger setup that goes on the Gladiator, and sae this same behavior. The fix was a table for the throttle body control that should not have needed touched from stock or at least that was is my opinion. This would would lend some credence to my thought if these are stock.

When I finally got my manual trans (emphasis on the manual), I noticed this surging/lugging (not actually lugging but it feels like it) behavior occasionally and immediately thought of your throttle oscillation issues you came across in your tuning. Seems 100% like a TB control issue. I have so few miles on my rig it can definitely still be learning and may go away. Easy fix is drive it more aggressively, which is very easy and rewarding with that 3rd pedal. I don't understand all the hate on the manual in the gladiator, it's awesome! I don't even mind the ratios..

 

[JWGladiator]

If the vehicle doesn't act up for them, has the latest software and there are no bulletins addressing your specific problem the dealership will have no idea what to do to repair it.

Yup. Hence the frustration. Going to keep driving it and see what it does.

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