EtBiart
Well-Known Member
- First Name
- ET
- Joined
- Aug 16, 2021
- Threads
- 36
- Messages
- 127
- Reaction score
- 78
- Location
- Long Island, NY
- Vehicle(s)
- Jeep Wrangler Unlimited Rubicon
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- Occupation
- Aircraft mechanic
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- #1
looking for all the help I can get. I've been in contact with several really nice members here but still no luck
I believe I have a transmission related issue.... also believe it could be transferase / torque converter or a bad TCM or valve body..
Facts: 2024 Rubicon. 2-door. 3.6L. Automatic. no FAD. Non torque. Part time 4wd.
She shifts up great. But when I get up to speed past 4th gear then either brake or coast , she lurches / jolts forward with an audible pop / clunk.... always when decelerating going past 4th gear. Doesn’t happen if I drive up to only 2nd or 3rd and brake/coast. Once it decelerates to 4th and it happens , it feels like the transmission is confused at 4th gear. so when coasting it slows it self down like an early downshift then pops and lurches forward.. sometimes I have to brake harder. it makes decelerating a pain in the ass..
a very similar pop / clunk is heard when taking my foot on an off the gas suddenly. that only happens when already rolling. never from start... and never past 7th gear. maybe I don't notice it in higher gears due to wind and road noise. Happens in all driving modes.
this started happening after the lift and re-gear.. first I thought it was normal. ( others convinced me it was normal ) then I thought it was the gears.
I re-geared and added a 2.5 AEV lift and 35" KO2 tires in the process. everything was done by a very reputable shop. Everything programmed correctly. Gears and tires
after the mods things got difficult.
it just made my life harder because the pop and lurch forward started to get more noticeable.. maybe because the shop guys told me they think I have a transmission problem.
So I brought it to a jeep dealer. They immediately blamed the differentials and lift without checking anything..
I brought it back to the shop and they re-checked all their work..
So i’m here doing my best to trouble shoot everything. I’m only at 4k miles. The engine hasn’t even broken in yet. Also, I get extremely low gas mileage. Way less than my 2.0 JLU on 37’s and 5:13 gears. On the JLU I average 17 MPG driving heavy footed. On the 2-door I get 13 MPG average driving light footed. I’m thinking that could be a bad TCM issue.
I still suspect the transfer case / torque converter, or maybe a bad valve body.
Here’s what I’ve done so far.
Drove in “manual” mode. Issue still present. I don’t know if that cancels it being the automatic transmission.
I lifted it the jeep and got into gear. Issue still present.
I removed the rear driveshaft. And drove around in 4HI. Issue still present. That should cancel it being the rear axle / diff.
I removed the front driveshaft and drove in 2HI. Issue still present. That should cancel it being the front axle / diff.
Tried all the relearns in JSCAN. No help
I dunno what else to do....
I’m taking it back to a Jeep dealer and going to try and prove it’s not the lift or axles.
In the meantime, im really hoping someone can help me figure it out, or someone with the same issue got it fixed. I’ve seen a few other people here with the same issue but they’ve disappeared off the forum and another just gave up.
If not, thanks for even making it this far. And listening.
I believe I have a transmission related issue.... also believe it could be transferase / torque converter or a bad TCM or valve body..
Facts: 2024 Rubicon. 2-door. 3.6L. Automatic. no FAD. Non torque. Part time 4wd.
She shifts up great. But when I get up to speed past 4th gear then either brake or coast , she lurches / jolts forward with an audible pop / clunk.... always when decelerating going past 4th gear. Doesn’t happen if I drive up to only 2nd or 3rd and brake/coast. Once it decelerates to 4th and it happens , it feels like the transmission is confused at 4th gear. so when coasting it slows it self down like an early downshift then pops and lurches forward.. sometimes I have to brake harder. it makes decelerating a pain in the ass..
a very similar pop / clunk is heard when taking my foot on an off the gas suddenly. that only happens when already rolling. never from start... and never past 7th gear. maybe I don't notice it in higher gears due to wind and road noise. Happens in all driving modes.
this started happening after the lift and re-gear.. first I thought it was normal. ( others convinced me it was normal ) then I thought it was the gears.
I re-geared and added a 2.5 AEV lift and 35" KO2 tires in the process. everything was done by a very reputable shop. Everything programmed correctly. Gears and tires
after the mods things got difficult.
it just made my life harder because the pop and lurch forward started to get more noticeable.. maybe because the shop guys told me they think I have a transmission problem.
So I brought it to a jeep dealer. They immediately blamed the differentials and lift without checking anything..
I brought it back to the shop and they re-checked all their work..
So i’m here doing my best to trouble shoot everything. I’m only at 4k miles. The engine hasn’t even broken in yet. Also, I get extremely low gas mileage. Way less than my 2.0 JLU on 37’s and 5:13 gears. On the JLU I average 17 MPG driving heavy footed. On the 2-door I get 13 MPG average driving light footed. I’m thinking that could be a bad TCM issue.
I still suspect the transfer case / torque converter, or maybe a bad valve body.
Here’s what I’ve done so far.
Drove in “manual” mode. Issue still present. I don’t know if that cancels it being the automatic transmission.
I lifted it the jeep and got into gear. Issue still present.
I removed the rear driveshaft. And drove around in 4HI. Issue still present. That should cancel it being the rear axle / diff.
I removed the front driveshaft and drove in 2HI. Issue still present. That should cancel it being the front axle / diff.
Tried all the relearns in JSCAN. No help
I dunno what else to do....
I’m taking it back to a Jeep dealer and going to try and prove it’s not the lift or axles.
In the meantime, im really hoping someone can help me figure it out, or someone with the same issue got it fixed. I’ve seen a few other people here with the same issue but they’ve disappeared off the forum and another just gave up.
If not, thanks for even making it this far. And listening.
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