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1999 GMC P Chassis 6.5L Upshift
Posted to GM Transmission on 2/10/2003 4 Replies

Customer has to let his foot off the accellerator to upshift. I found this vehicle will upshift into 2nd gear only when throttle is below 60% and into 3rd gear only when throttle is below 50%. When commanded with Tech 2 trans shifts fine. Plugged in new TCM, n...

4 Replies Received (View Replies)

 
Message Closed w/FIX

car Vehicle Data

1999 GMC P Chassis

VIN [No VIN Available]
Engine6.5 L / 8 cyl
DeliveryFI
AffectedUpshift
ConditionsLate
Misc.4L80e
Message Closed w/FIX

car Vehicle Data

1999 GMC P Chassis

VIN [No VIN Available]
Engine6.5 L / 8 cyl
DeliveryFI
AffectedUpshift
ConditionsLate
Misc.4L80e