2003 GMC Safari Brake Service (ONLINE REPAIR MANUALS)

Removal

• Remove caliper as outlined in. "Caliper Service."
• Remove inboard pad with retainer spring.
• Remove outboard pad and position caliper on front suspension so brake hose will not support weight of caliper.
• Remove two sleeves from inboard ears of caliper.
• Remove four rubber bushings from grooves in each of caliper ears.

Installation

• Lubricate new sleeves, rubber bushings, bushing grooves and mounting bolt ends with lubricant part No. 19010909, or equivalent.
• Install new bushings and sleeves in caliper ea...

General System

• Inspect components for damage or unusual wear. Replace as required.
• Inspect backing plate mounting bolts and ensure they are tight.
• Inspect wheel cylinders. Excessive fluid indicates cup leakage and need for wheel cylinder replacement. Slight amount of fluid is always present and is considered normal, acting as lubricant for cylinder pistons.
• Inspect adjuster screw operation. If satisfactory, lightly lubricate adjusting screw and washer with suitable brake lube. If operation is unsatisfactory, replace.
• Clean rust and dirt from shoe contact surfaces on backing plate using fi...

Disassemble

• Place accumulator compressor tool No. J-26889, or equivalent, around end of accumulator.
• Install nut onto stud as in. Fig. , then depress accumulator with a C-clamp.
• Remove retainer by using a punch.
• Release C-clamp and remove accumulator compressor tool.
• Remove accumulator, O-ring, retainer, plug and spring,. Fig. .
• Remove retainer, output pushrod, baffle, piston return spring and retainer.
• Cut off eyelet of pedal rod, then remove boot.
• Remove nut, bracket and bolts, then separate cover from housing.
• Remove piston assembly and seals.
• Remove spool valve, then the accu...

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.. Ensure 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. To bleed master cylinder, proceed 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...

Removal

Front

• Siphon brake fluid out of master cylinder until fluid level is approximately ^1/3 full, this will prevent fluid overflow when caliper piston is pushed back into its bore.
• Raise and support vehicle, then remove wheels.
• Push piston back into its bore using suitable C-clamp,. Fig. .
• Remove brake caliper hose bolt, then two metal gaskets from brake caliper bolt.
• Remove two caliper mounting bolts and lift caliper off of rotor.

Rear

Except S & T

• Siphon brake fluid out of master cylinder until fluid level is approximately ^1/3 full, this will prevent fluid overflow when caliper pist...

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, ensure all dirt is kept out of the system. Additionally, 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 brakes will still operate, as the convention...