Auto Parts Search

We have info for following modifications of 1991 GMC G25/G2500 VAN
- 1991 GMC G25/G2500 VAN Rally 4.3 V6 GAS, CID:262, Fuel Injection, Aspiration:262, Engine VIN:, Desg:Z
- 1991 GMC G25/G2500 VAN Rally 6.2 V8 DIESEL, CID:379, Fuel Injection, Aspiration:379, Engine VIN:, Desg:C
- 1991 GMC G25/G2500 VAN Rally 5.0 V8 GAS, CID:305, Fuel Injection, Aspiration:305, Engine VIN:, Desg:H
- 1991 GMC G25/G2500 VAN Rally 5.7 V8 GAS, CID:350, Fuel Injection, Aspiration:350, Engine VIN:, Desg:K
- 1991 GMC G25/G2500 VAN Vandura 4.3 V6 GAS, CID:262, Fuel Injection, Aspiration:262, Engine VIN:, Desg:Z
- 1991 GMC G25/G2500 VAN Vandura 6.2 V8 DIESEL, CID:379, Fuel Injection, Aspiration:379, Engine VIN:, Desg:C
- 1991 GMC G25/G2500 VAN Vandura 5.0 V8 GAS, CID:305, Fuel Injection, Aspiration:305, Engine VIN:, Desg:H
- 1991 GMC G25/G2500 VAN Vandura 5.7 V8 GAS, CID:350, Fuel Injection, Aspiration:350, Engine VIN:, Desg:K
BRAKE SERVICE PROCEDURES FOR 1991 GMC G25/G2500 VAN AUTOMOBILES
Includes anti-lock brakes, disc, drum, power and hydraulic brake services diagnostics and procedures for domestic and imported 1991 GMC G25/G2500 VAN cars and light trucks from 1990+.
ANTI-LOCK BRAKES, GENERAL MOTORS -> Four Wheel Anti-Lock Brake System -> SYSTEM SERVICE -> BLEEDING EHCU MODULE
Vehicle: 1991 GMC G25/G2500 VAN Vandura 4.3 V6 GAS
BLEEDING EHCU MODULE
The EHCU Module should be bled after replacement or if trapped air is in the unit. If bleeding is required the module must be bled thoroughly before the wheel cylinders and calipers.
There are two bleeders on top of the unit that appear to be normal bleeders, Fig. . These are modulator bleeders and must remain closed when the unit is not pressurized.
The internal bleeders are on either side of EHCU module. The valves are used to open the internal passages within the EHCU module. Both bleed valves must be rotated 1/4-1/2 a turn counterclockwise before beginning t...
CLICK HERE TO GET FULL ACCESS TO 1991 GMC G25/G2500 VAN BRAKE SERVICE PROCEDURES
BRAKE SERVICE PROCEDURES FOR 1991 GMC G25/G2500 VAN AUTOMOBILES
Includes anti-lock brakes, disc, drum, power and hydraulic brake services diagnostics and procedures for domestic and imported 1991 GMC G25/G2500 VAN cars and light trucks from 1990+.
POWER BRAKE UNITS, GENERAL MOTORS -> Tracker Brake Booster -> IN-VEHICLE SERVICE -> BOOSTER PISTON ROD ADJUSTMENT
Vehicle: 1991 GMC G25/G2500 VAN Rally 4.3 V6 GAS
BOOSTER PISTON ROD ADJUSTMENT
- Pump brake pedal several times, then remove master cylinder from brake booster.
- With gasket installed on master cylinder, install booster piston rod gauge tool No. J34873-A or equivalent on master...
CLICK HERE TO GET FULL ACCESS TO 1991 GMC G25/G2500 VAN BRAKE SERVICE PROCEDURES
BRAKE SERVICE PROCEDURES FOR 1991 GMC G25/G2500 VAN AUTOMOBILES
Includes anti-lock brakes, disc, drum, power and hydraulic brake services diagnostics and procedures for domestic and imported 1991 GMC G25/G2500 VAN cars and light trucks from 1990+.
DISC BRAKES, GENERAL MOTORS -> Delco-Moraine Single Piston Caliper -> CALIPER SERVICE -> ASSEMBLE -> DISASSEMBLE -> INSTALLATION -> REMOVAL
Vehicle: 1991 GMC G25/G2500 VAN Rally 4.3 V6 GAS
REMOVAL
- Siphon enough brake fluid out of the master cylinder to bring fluid level to1-3 full to avoid fluid overflow when the caliper piston is pushed back into its bore.
- Raise and support vehicle, remove front wheels.
- Using a C-clamp, as illustrated in Fig. , push piston back into its bore.
- Remove two mounting bolts and lift caliper away from disc.
DISASSEMBLE
- Disconnect hose from the caliper being careful not to lose copper washers.
- Remove caliper as outlined above.
- Drain brake fluid from caliper.
- Pad caliper interior with clean shop towels and apply compressed air to remove piston, Fi...
CLICK HERE TO GET FULL ACCESS TO 1991 GMC G25/G2500 VAN BRAKE SERVICE PROCEDURES
BRAKE SERVICE PROCEDURES FOR 1991 GMC G25/G2500 VAN AUTOMOBILES
Includes anti-lock brakes, disc, drum, power and hydraulic brake services diagnostics and procedures for domestic and imported 1991 GMC G25/G2500 VAN cars and light trucks from 1990+.
ANTI-LOCK BRAKES, GENERAL MOTORS -> Four Wheel Anti-Lock Brake System -> COMPONENT REPLACEMENT -> EHCU MODULE -> FRONT WHEEL SPEED SENSOR -> REAR WHEEL SPEED SENSOR
Vehicle: 1991 GMC G25/G2500 VAN Vandura 5.7 V8 GAS
EHCU MODULE
The EHCU module is not serviceable and must be replaced as a unit. Refer to Fig. when replacing the unit.
- Bleed brake booster by depressing brake pedal several times.
- Remove washer tank attaching bolts, then position aside.
- Remove EHCU electrical connectors.
- Disconnect module brake lines. Use caution not to get brake fluid on paint or electrical connections.
- Remove upper to lower bracket assembly attaching bolts.
- Remove EHCU module and upper bracket assembly from vehicle.
- Remove upper mounting bracket to EHCU module attaching bolts.
- Reverse procedure to install, noting...
CLICK HERE TO GET FULL ACCESS TO 1991 GMC G25/G2500 VAN BRAKE SERVICE PROCEDURES
BRAKE SERVICE PROCEDURES FOR 1991 GMC G25/G2500 VAN AUTOMOBILES
Includes anti-lock brakes, disc, drum, power and hydraulic brake services diagnostics and procedures for domestic and imported 1991 GMC G25/G2500 VAN cars and light trucks from 1990+.
ANTI-LOCK BRAKES, GENERAL MOTORS -> Four Wheel Anti-Lock Brake System -> SYSTEM SERVICE -> BLEEDING EHCU MODULE
Vehicle: 1991 GMC G25/G2500 VAN Rally 4.3 V6 GAS
BLEEDING EHCU MODULE
The EHCU Module should be bled after replacement or if trapped air is in the unit. If bleeding is required the module must be bled thoroughly before the wheel cylinders and calipers.
There are two bleeders on top of the unit that appear to be normal bleeders, Fig. . These are modulator bleeders and must remain closed when the unit is not pressurized.
The internal bleeders are on either side of EHCU module. The valves are used to open the internal passages within the EHCU module. Both bleed valves must be rotated 1/4-1/2 a turn counterclockwise before beginning t...
CLICK HERE TO GET FULL ACCESS TO 1991 GMC G25/G2500 VAN BRAKE SERVICE PROCEDURES
BRAKE SERVICE PROCEDURES FOR 1991 GMC G25/G2500 VAN AUTOMOBILES
Includes anti-lock brakes, disc, drum, power and hydraulic brake services diagnostics and procedures for domestic and imported 1991 GMC G25/G2500 VAN cars and light trucks from 1990+.
DISC BRAKES, GENERAL MOTORS -> Delco-Moraine Single Piston Caliper -> BRAKE PAD, Replace -> INSTALLATION -> REMOVAL
Vehicle: 1991 GMC G25/G2500 VAN Vandura 5.0 V8 GAS
REMOVAL
- Remove caliper assembly as outlined above.
- Remove inboard pad with retainer spring. Dislodge outboard pad and position caliper on the front suspension so the brake hose will not support the weight of the caliper.
- Remove two sleeves from inboard ears of the caliper.
- Remove four rubber bushings from the grooves in each of the caliper ears.
INSTALLATION
- Lubricate new sleeves, rubber bushings, bushing grooves and mounting bolt ends with Delco Silicone Lube or equivalent.
- Install new bushings and sleeves in caliper ears. Position the sleeve so that the end toward the pad is flush...
CLICK HERE TO GET FULL ACCESS TO 1991 GMC G25/G2500 VAN BRAKE SERVICE PROCEDURES
Shop online for auto body parts, engines, wheels, lights...
More parts |
Get the Complete Technical Service Bulletins! |
![]() |
Access the Complete guide! |