R 3500 P/U 2WD V8-454 7.4L VIN W 4-bbl (1988)
Shift Modulator: Service and Repair
Turbo Hydra-Matic 3L80 & 3L80HD (400 & 475)
1.
Remove modulator attaching screw and retainer.
2.
Remove modulator assembly from case and discard O-ring seal.
3.
Remove modulator valve from case.
4.
Reverse procedure to install, using a new O-ring seal.