1996 Chevrolet K2500 Pickup Brake Service (ONLINE REPAIR MANUALS)

Service Brake

Except 1992-94 Lumina APV, Silhouette & Trans Sport

These brakes have self-adjusting shoe mechanisms that assure correct lining-to-drum clearances at all times. The automatic adjusters operate only when the brakes are applied as the vehicle is moving rearward or when the car comes to an uphill stop.

Although the brakes are self-adjusting, an initial adjustment is necessary after the brake shoes have been relined or replaced, or when the length of the adjusting screw has been changed during some other service operation.

Frequent usage of an automatic transmission forward ra...

Delco-Moraine Master Cylinder

Composite Type

When performing the following procedures, refer to Fig. for all models except Lumina APV, Silhouette & Trans Sport, noting that the composite reservoir may vary in design. Refer to Fig. for Lumina APV, Silhouette & Trans Sport models.

Disassemble

• Remove master cylinder from vehicle.
• Remove reservoir cover and diaphragm. Discard old brake fluid in reservoir.
• Inspect cover and diaphragm. Replace if cut, cracked or deformed.
• Remove fluid level switch and proportioning valve assembly, if equipped.
• Depress primary piston and remove lock ring.
• P...

Height Sensing Proportioning Valve

The height sensing proportioning valve must be adjusted whenever the valve and/or linkage is disassembled or removed for service. In addition, adjustment should be checked if excessive front wheel lock-up is experienced with a lower than desired brake application rate when vehicle is at or near maximum GVWR.

• Raise and support vehicle leaving wheels on, and allow axle to hang freely.
• Remove lever retaining nut and disconnect lever from valve shaft, Fig. .
• Rotate valve shaft to permit installation of correct adjustment gauge, Fig. , ensuring that D shape...

In order to properly service power brake systems, a thorough understanding of the power assist system is necessary. These systems provide a mechanical assist, acting to increase the force applied to the master cylinder piston by the driver while decreasing the effort necessary to obtain acceptable stopping performance.

Hydraulic assist units incorporate a basic open center spool valve, hydraulic cylinder and an accumulator assembly in a common housing. When the brake pedal is depressed, the hydraulic piston moves forward closing off fluid relief passages, the spool valve applies flui...

Manual Bleed

• If vehicle is equipped with power brakes, remove vacuum reserve by applying brakes several times with engine off.
• Fill master cylinder reservoirs with suitable brake fluid. Be sure to always keep master cylinder reservoirs at least half full during entire bleeding procedure.
• If master cylinder is suspected to have air in the bore, it must be bled first, as follows:
• Disconnect forward brake pipe connection at master cylinder.
• Allow brake fluid to fill master cylinder bore until it begins to flow from forward pipe connector port.
• Connect and tighten forward brake pipe at...

Certain general service procedures apply, regardless of whether the brakes are vacuum or hydraulically assisted. Only top quality, clean brake fluid should be used. More seals and valves are used with power brake systems than with ordinary brakes, so an inferior brake fluid will do much more damage. For the same reason, be sure all dirt is kept out of the system. Additionally, on models with hydraulic assist brakes, care must be taken not to mix the fluids of the booster hydraulic system and brake hydraulic system as the fluids are not compatible.

If the power unit fails, the bra...