G 2500 3/4 Ton Van V6-262 4.3L VIN Z (1992)
Accumulator: All Technical Service Bulletins
A/T - Harsh 1-2 Upshift
BULLETIN NUMBER: 92-7A-145
SECTION: 7A
NUMBER: 5
CORPORATE
REFERENCE NUMBER: 277135R
DATE: November 1992
SUBJECT:
HARSH 1-2 UPSHIFT (INSTALL SERVICE PACKAGE)
MODELS:
1992 C/K, S/T TRUCKS AND M/L/G VANS WITH 4L60 TRANSMISSION
CONDITION (Figure 1):
Some vehicles equipped with a 1992 HYDRA-MATIC 4L60 transmission built between Julian Date 061 (March 1, 1992) and Julian Date 171 (June 19,
1992) may experience a harsh 1-2 upshift.
NOTE:
Once the transmission is brought to operating temperature, the condition may not be able to be reproduced until a "cold soak" (overnight) is performed.
CAUSE:
The above condition may be caused due to a tapered 1-2 accumulator sleeve. The tapered bore may cause the 1-2 accumulator valve to stick in the
bottom of the bore.
