Adaptive transmission
Thread Starter
Instructor
Joined: Feb 2005
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Adaptive transmission
I have a 2016 Z51 with an A8, with only have 200 miles on the car. It definitely has the new part number on the transmission. i noticed that when I get on the car "a bit" it was shifting hard in 2nd & 3rd, and made a sort of "clacking" noise when it shifted. I called the service department and Im being told that the "adaptive" 8 speed transmission goes through a "learning process" before it settles in, and to give it a few hundred more miles. Is there a proper way to break in the A8? I mean,... If you go easy on the car for the first 500-1500 miles, how is the transmission "adapting" to a driving style that doesn't reflect what will become the normal type of driving after the engine break in period?? How long does the transmission continue to adapt?
Any information on the "adaptive" process, or how to properly break in the A8 would be appreciated.
Thanks!
Any information on the "adaptive" process, or how to properly break in the A8 would be appreciated.
Thanks!
Instructor
Joined: May 2014
Posts: 124
Likes: 9
From: WA
I have a 2016 Z51 with an A8, with only have 200 miles on the car. It definitely has the new part number on the transmission. i noticed that when I get on the car "a bit" it was shifting hard in 2nd & 3rd, and made a sort of "clacking" noise when it shifted. I called the service department and Im being told that the "adaptive" 8 speed transmission goes through a "learning process" before it settles in, and to give it a few hundred more miles. Is there a proper way to break in the A8? I mean,... If you go easy on the car for the first 500-1500 miles, how is the transmission "adapting" to a driving style that doesn't reflect what will become the normal type of driving after the engine break in period?? How long does the transmission continue to adapt?
Any information on the "adaptive" process, or how to properly break in the A8 would be appreciated.
Thanks!
Any information on the "adaptive" process, or how to properly break in the A8 would be appreciated.
Thanks!
Safety Car
Joined: Aug 2012
Posts: 3,960
Likes: 1,106
The "clacking" noise you hear during high throttle shifts may be from the engine. Spark is interrupted briefly during the shift to allow much faster shifts AND the noise is entirely normal.
The transmission does have adaptive learning however it is intended to provide firm shifts when required/desired and these will continue under high throttle conditions. Although adaptive learning is influenced by driving style it is learning clutch pack slippage based upon hydraulic pressure throughout the shift event and this information is used to "trim" the apply pressure differently based upon different driving conditions. So what it learns helps it to perform better during all driving styles and not just a specific type of operation.
Just continue to drive your A8 under a variety of conditions during its "Kindergarten" period and it should adapt normally. Adaptive transmissions aren't new to GM and the Allison automatic (at that time fully owned by GM)I had in my 2001 GMC pickup was a clutch to clutch architecture adaptive transmission (like the 8L90) and also went through a fast learning process during the first few hundred miles of operation. These adaptive transmissions continue to adapt over the life of the unit to compensate for normal wear.
The transmission does have adaptive learning however it is intended to provide firm shifts when required/desired and these will continue under high throttle conditions. Although adaptive learning is influenced by driving style it is learning clutch pack slippage based upon hydraulic pressure throughout the shift event and this information is used to "trim" the apply pressure differently based upon different driving conditions. So what it learns helps it to perform better during all driving styles and not just a specific type of operation.
Just continue to drive your A8 under a variety of conditions during its "Kindergarten" period and it should adapt normally. Adaptive transmissions aren't new to GM and the Allison automatic (at that time fully owned by GM)I had in my 2001 GMC pickup was a clutch to clutch architecture adaptive transmission (like the 8L90) and also went through a fast learning process during the first few hundred miles of operation. These adaptive transmissions continue to adapt over the life of the unit to compensate for normal wear.
Last edited by NSC5; Feb 23, 2016 at 11:04 AM.
Racer
Joined: Dec 2013
Posts: 327
Likes: 17
I have a 2016 Z51 with an A8, with only have 200 miles on the car. It definitely has the new part number on the transmission. i noticed that when I get on the car "a bit" it was shifting hard in 2nd & 3rd, and made a sort of "clacking" noise when it shifted. I called the service department and Im being told that the "adaptive" 8 speed transmission goes through a "learning process" before it settles in, and to give it a few hundred more miles. Is there a proper way to break in the A8? I mean,... If you go easy on the car for the first 500-1500 miles, how is the transmission "adapting" to a driving style that doesn't reflect what will become the normal type of driving after the engine break in period?? How long does the transmission continue to adapt?
Any information on the "adaptive" process, or how to properly break in the A8 would be appreciated.
Thanks!
Any information on the "adaptive" process, or how to properly break in the A8 would be appreciated.
Thanks!
Can you please explain what you mean by "new part number on the transmission"?
I have an early 2015 Z51 with an A8 and it has at least the notorious "harsh shifting" problem and would like to know if there is a newer version of the A8 than the one in my car.
Thanks for any help you can lend.
Thread Starter
Instructor
Joined: Feb 2005
Posts: 151
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There was a thread entitled "A8 issues" that discusses the replacement transmission that resolved the problems being experienced on the 2015 A8. Apparently the changeover began in mid October 2015. The newer P/N is 24275892, the part it replaced is 24273222. I don't know how to attach pictures on the thread, if you pm me your email address I will show you where the P/N is located.
thanks for the information about the A8.
Can you please explain what you mean by "new part number on the transmission"?
I have an early 2015 Z51 with an A8 and it has at least the notorious "harsh shifting" problem and would like to know if there is a newer version of the A8 than the one in my car.
Thanks for any help you can lend.
Can you please explain what you mean by "new part number on the transmission"?
I have an early 2015 Z51 with an A8 and it has at least the notorious "harsh shifting" problem and would like to know if there is a newer version of the A8 than the one in my car.
Thanks for any help you can lend.
