A/T - 440T4/4T60 Late or No Upshift
DATE: 1995TECHNICAL BULLETIN # 301
TRANSMISSION: 440-T4 / 4T60
SUBJECT: Late or No Upshift
APPLICATION: GM
A late or no upshift (shifts at 1-2 WOT only) condition can be caused by a worn or seized T.V. plunger and sleeve assembly. When replacing a TV plunger and sleeve, be aware that several assemblies are available from G.M. They are identified by a letter stamped in the side of the sleeve, as shown in the illustration.
The difference in the sleeves is the location of the part throttle feed hole. This determines at what throttle opening the part throttle 3-4 upshift and 4-3 downshifts shifts will occur.
Example: The "P" sleeve delivers part throttle at approximately 50% throttle, while the "K" sleeve delivers part throttle at approximately 90% throttle.