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Discussion Starter #1
I've just finished a transmission swap, and I was wondering if the transmission adapt reset has to be done or if it learns by itself. The transmission currently acts like a normal transmission, but the FSM tells me to reset it in red and bold letters.

Is it required because of a potential customer complaint (maybe it causes erratic behaviors that was "adapt" for the original transmission? :noidea:) or it just has to be done? I don't want to do it (don't want to pay dealer $$$ for some Tech-II work) if it doesn't have to be done, since the transmission works fine.
 

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1999 Seville STS, 2004 Deville DHS
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Adapt Function

The 4T80-E transmission uses a line pressure control system, which has the ability to continuously adapt the system's line pressure. This compensates for normal wear of the following parts:

The clutch fiber plates
The seals
The springs

The PCM maintains the following adapt parameters for the transmission:

Upshift Adapt - The PCM monitors the Automatic Transmission Input(Shaft) Speed Sensor (A/T ISS) and the Vehicle Speed Sensor (VSS) during commanded shifts in order to determine if a shift is occurring too fast or too slow. The PCM adjusts the signal to the transmission pressure control solenoid valve in order to maintain a set shift feel.
Steady State Adapt - The PCM monitors the Automatic Transmission Input(Shaft) Speed Sensor (A/T ISS) and the Vehicle Speed Sensor (VSS) after a shift and the PCM calculates the amount of slippage in that gear. The PCM then adjusts the signal to the transmission pressure control solenoid valve in order to maintain slippage below a set amount.
Garage Shift Adapt - The PCM monitors the Automatic Transmission Input(Shaft) Speed Sensor (A/T ISS) during a shift into a given range (P,R,N,D) and the PCM calculates whether the engagement is occurring too fast or too slow. The PCM adjusts the PC solenoid valve in order to maintain a set shift feel.
WOT 1-2 Adapt - The PCM monitors the Vehicle Speed Sensor (VSS) and the engine rpm during a 1-2 Wide Open Throttle (WOT) shift. The PCM will adapt the 1-2 shift point during WOT.
Learn Tap - Accelerated PLM learn mode. A technician must road test the vehicle for 15 minutes (normal time 2-3 hrs).

Important

The transmission may experience harsh, soft or mushy shifts for up to two days later.


Transmission adapts must be reset whenever the transmission is overhauled or replaced. In order to reset transmission adapts, select the following:

Scan tool
Miscellaneous test
A/T outputs
Clear or reset all adapts

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I don't think you need to go and clear it. You'll likely get somewhat harsh shifts but I interpret that bit in red to say that if you don't reset the adapts it'll self-learn by itself. I'd exercise all the adapts, you'll do most of them in normal driving except the 1-2 WOT upshift.
 

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Discussion Starter #3
I guess not. I just worried about it since the FSM stated like it was required. Well, it's showing no problems and the shifts are getting smoother than the first day I guess, so I'd think I don't need to manually reset it.

Thank you for your reply.
 
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