Jeep Trans Map

Hey all,

I have a 2014 Grand Cherokee SRT and in stock form I get clunky shifts. My Jeep was built in mid 2013 and has the 8HP70. I am tuned but it makes the shifting behavior worse. Has anyone seen where the early 8 speeds have terrible maps and terrible converter lockups? I have gone through a lot of the drivetrain to see if I can see anything loose or any issue and I have not seen anything. Everything looks great. My main complaint is when I am stopping I get some clunks and shudder. Also when accelerating or taking my foot off of the gas and reapplying it it feels like it clunks sometimes. I took a quick drive around the block and logged some parameters. Don't know what im looking at since im so green to tuning.

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Originally Posted by mc.keefner

Hey all,

I have a 2014 Grand Cherokee SRT and in stock form I get clunky shifts. My Jeep was built in mid 2013 and has the 8HP70. I am tuned but it makes the shifting behavior worse. Has anyone seen where the early 8 speeds have terrible maps and terrible converter lockups? I have gone through a lot of the drivetrain to see if I can see anything loose or any issue and I have not seen anything. Everything looks great. My main complaint is when I am stopping I get some clunks and shudder. Also when accelerating or taking my foot off of the gas and reapplying it it feels like it clunks sometimes. I took a quick drive around the block and logged some parameters. Don't know what im looking at since im so green to tuning.

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Driveline clunks slowing to a stop or accelerating from a stop are extremely common in all WK2 Jeeps.

Have you tried resetting your adaptives?

Yes multiple times. I have done most of everything I can think of. I had a 2015 Grand cherokee 5.7 Overland and it was smooth as glass. Probably the best trans I have felt. They have the same exact trans,transfer case but different rear end. That is why I am confused why this one feels so much clunkier. It could be the rear end as it is a 3.70 compared to the 3.09 I had and it is an SRT and I have read they are a lot more raw. I think I am so cautious because I have wanted an Jeep SRT since highschool so it is a dream car and I want to make sure nothing is wrong with it.

Mine clunks with only 30k

What year is yours? I took it in to the dealer and they did a pretty deep look and updated everything but funny enough there was ECU updates but nothing for the trans. I wan to go test drive one this weekend and see if they behave similar. That may put my mind to rest. But probably not lol

Quote:

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Originally Posted by mc.keefner

What year is yours? I took it in to the dealer and they did a pretty deep look and updated everything but funny enough there was ECU updates but nothing for the trans. I wan to go test drive one this weekend and see if they behave similar. That may put my mind to rest. But probably not lol

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Mines a 2014

Post up your tune


Im sure mine has had the clunk its whole life and the first owner had them change out the differential according to CarFAX. I still have it, probably why they got rid of it. I've just learned to ignore it

Here is the stock tune for it that has clunks

From driving around and doing some monitoring it looks like it could be the TC lockup and weird times making it clunky. On the 4-3 downshift it looks like while im stopping it shifts down from 5 to 4 then locks up then downshifts to 3 and makes it seem like a driveline clunk.