Jimmy Full Size L6-250 4.1L (1982)
Accumulator: Customer Interest
A/T - No Engine Braking In Drive 2 (D2) Selection
GMC NUMBER:
88-T-200
GROUP:
7A - Automatic Transmission
DATE:
February, 1989
CORPORATE
NUMBER:
877137
SUBJECT:
NO ENGINE BRAKING IN DRIVE 2 (D2)
MODELS:
1978-88 TRUCKS WITH THM 400/475 TRANSMISSION
BULLETIN COVERS:
No engine braking in Drive 2 (D2) selector range caused by a broken plastic Front Accumulator Piston (303). The transmissions affected are the THM
400/475/HYDRA-MATIC 3L80/3L80-HD Transmission. The die cast aluminum piston can be used in service for this condition and will reduce the
chance of any broken or cracked pistons.
Figure No. 1 - THM 400/475, HYDRA-MATIC 3L80/3L80-HD Transmission Identification Information
DATE OF PRODUCTION CHANGE: (Figure 1)
August 1, 1988 (Julian Date 214) all 1989 THM 400/475/HYDDA-MATIC 3L80/3L80-HD Transmissions were built with the aluminum Front
Accumulator Piston (303).
