C 3500 Truck 2WD V8-454 7.4L (1990)
Transmission Vacuum Regulator Valve: Service and Repair
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.