Driveline slop with automatic transmission

CybrSlydr

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I've experienced this with just about any automatic transmission vehicle I've driven, but seems a bit more pronounced in this Rubicon.

Especially after start-up. For instance, driving around town at 25-35mph, I can let off the gas and then get back on it and there is a half-second or so delay before the transmission catches up with the pedal and you get a good jerk. After driving around for a bit, it seems to go away for the most part.

Or when leaving work, I turn to go up a hill and the engine will rev higher than normal and it feels like it's trying to shift, but misses and then there's a big lurch, few seconds later the revs go down like it's found it's gear.

Is this an issue with the transmission? Something I should be concerned about?
 
That to me sounds more like symptoms of a slipping transmission.

I'd start by changing the fluid and checking the fluid level.
 
That to me sounds more like symptoms of a slipping transmission.

I'd start by changing the fluid and checking the fluid level.

Fluid was changed by Valvoline back in May.

– Rear Diff Fluid Replacement
– Automatic Trans Fluid Replace
– Transfer Case Fld Replacement
– Front Diff Fluid Replacement
– Full Synthetic MaxLife Oil Change
 
It stands to reason then that it could be time for a rebuild. Generally they don't make it past 150k before they start slipping and need a rebuild. What you're describing sounds to me like what is happening.
 
Before thinking rebuild at only 118k miles, be sure to check the transmission's ATF level correctly. To check the ATF level, the engine MUST be running and the transmission MUST be shifted to Neutral when checking it with the transmission's dipstick.

If the engine isn't running or if it's in park you'll get an erroneously level reading indicating there's more ATF than there really is. If it's low, make sure to ONLY add ATF+4 and let's hope those Valvoline guys knew to only add ATF+4 to your transmission. I wouldn't be surprised that the Valvoline quick lube place checked the level with the transmission in Park and thought it was fuller than it really is and left it low on ATF+4.
 
^^ Agree Completely with Jerry... Make sure you check it correctly... There is a difference; we once had a shop tell us the trans was overfilled & they should have us service it.. it because they were not checking it correctly...

Also hopefully they put ATF+4 in it....
 
I'd add that the 42RLE is a total mess on even the best days, don't expect miracles. Just keep it cool, keep it serviced and live with the madness.
 
I'd add that the 42RLE is a total mess on even the best days, don't expect miracles. Just keep it cool, keep it serviced and live with the madness.
My 42RLE works fine once I installed the right ratio r&p gears. No problems. I just drove it 1200 miles 2 weeks ago and never gave it a second thought.
 
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I'll give it a look on Friday - dunno if I want it to be low ATF or not. lol Fluid is certainly less expensive than transmission rebuild.

Thing is about every other weekend, I'm putting about 180mi on it fishing and it's been just fine after it warms up a bit.
 
I'll give it a look on Friday - dunno if I want it to be low ATF or not. lol Fluid is certainly less expensive than transmission rebuild.

Thing is about every other weekend, I'm putting about 180mi on it fishing and it's been just fine after it warms up a bit.
You haven't checked that ATF level yet!!?? Come on, it only takes like 3 minutes to do. Keep in mind the correct procedure given in post #8 above. For all we know the ATF could be full but if it's not, being too low can damage the transmission and cause it to get hotter than it should since it's the ATF that cools it. Checking the level is not something you should delay doing. @CybrSlydr
 
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You haven't checked that ATF level yet!!?? Come on, it only takes like 3 minutes to do. Keep in mind the correct procedure given in post #8 above. For all we know the ATF could be full but if it's not, being too low can damage the transmission and cause it to get hotter than it should since it's the ATF that cools it. Checking the level is not something you should delay doing. @CybrSlydr

I'm pretty sure it'll take even less than 3min. :)

I've been driving the M3, so it's not been as pressing an issue. Plus, when I've had the chance, the weather has been ugly down here.
 
Most autos have to be warmed up too. A cold start, throw it In neutral and check the stick will show different than having the engine and trans st normal running temp. Never had an auto Jeep, so I may be wrong. But still, checking the dipstick takes seconds. You won't melt if there is rain. Ruining the tranny because you don't have time? You could have checked it a dozen times for the time you used to ask what to do.
 
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