Buick LeSabre 1986-1999
Buick Park Avenue 1996-1999
Oldsmobile 88 1992-1999
Oldsmobile Delta 88 1986-1988
Oldsmobile LSS 1996-1999
Pontiac Bonneville 1987-1999
For 1986-91 vehicles equipped with ABS, the entire Hydraulic Assembly must be removed along with the master cylinder. Please refer to the procedure, located under the Teves Mark II ABS system in this section. For 1992-99 vehicles, the master cylinder can be removed independently of the ABS components.
For 1992-99 vehicles with ABS, after bleeding the brake system you must perform an "Auto Bleed" sequence, using a Tech 1® or equivalent scan tool. If you do not have access to a suitable scan tool, your vehicle will probably have to be towed to a shop with the proper diagnostic equipment to have the procedure performed.
Removal & Installation
Brake fluid contains polyglycol ethers and polyglycols. Avoid contact with the eyes and wash your hands thoroughly after handling brake fluid. If you do get brake fluid in your eyes, flush your eyes with clean, running water for 13 minutes. If eye irritation persists, or if you have taken brake fluid internally, IMMEDIATELY seek medical assistance.
Disconnect the negative battery cable.
Use a turkey baster or equivalent tool to siphon the brake fluid from the master cylinder into a suitable container.
Clean, high quality brake fluid is essential to the safe and proper operation of the brake system. You should always buy the highest quality brake fluid that is available. If the brake fluid becomes contaminated, drain and flush the system, then refill the master cylinder with new fluid. Never reuse any brake fluid. Any brake fluid that is removed from the system should be discarded. Also, do not allow any brake fluid to come in contact with a painted surface; it will damage the paint.
If equipped, unfasten the retainer and detach the electrical connector from the fluid level sensor.
For 1991-99 vehicles with ABS, disconnect the reservoir hose and plug it to avoid contamination and fluid loss.
Fig. For 1991-99 ABS equipped vehicles, disconnect and plug the reservoir hose
Use a flare nut wrench to disconnect the hydraulic lines from the master cylinder. Plug or cap the lines to avoid contaminating the system.
Unfasten the master cylinder-to-power booster mounting bolts/nuts, then remove the master cylinder assembly.
On 1991-99 ABS equipped vehicles, if replacing the master cylinder, transfer the reservoir to the new master cylinder.
Fig. Exploded view of the master cylinder-to-power booster attachment - 1954-90 vehicles without ABS
Fig. Master cylinder removal and installation - 1991-92 vehicles
Fig. Exploded view of the master cylinder mounting - 1993-99 vehicles
Fig. Master cylinder components - 1993 vehicle shown, other year similar
Install the master cylinder assembly to the power booster and secure with the mounting bolts/nuts. Tighten to 20 ft. lbs. (24 Nm).
Unplug and connect the hydraulic lines to the master cylinder. Tighten the lines to 11 ft. lbs. (13 Nm), using a flare nut wrench.
For 1991-99 ABS equipped vehicles, unplug and connect the reservoir hose assembly.
If equipped, attach the electrical connector to the fluid level sensor and secure with the retainer, if applicable.
Connect the negative battery cable.
Refill the master cylinder with clean brake fluid from a fresh, sealed container. Bleed the brake system as outlined in this section, then recheck the fluid level.