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Buick Brake Booster Problems and Troubleshooting

Where could a Buick be losing fluid when there is no visible leak? Do Buick brakes have to be replaced frequently? Brakes are a safety issue on which there is zero tolerance, so the first sign of a brake problem needs immediate attention. Most brake problems are caused by a bad brake booster, but to be certain, pass the symptoms on to an Expert for a customized answer.

Read below about some brake booster problems Buick owners have encountered and how Experts have helped by answering their questions.

Is your Buick LeSabre losing brake fluid?

See if there is a leak at the rear wheel cylinders and inspect the lines carefully for signs of seepage. If nothing can be found unbolt the master cylinder and look for brake fluid in the power brake booster. If brake fluid is visible then the booster is draining fluid out of the master cylinder through its rear end. This indicates that the booster is bad and should be replaced.

How to troubleshoot a Buick Regal brake booster which is unable to hold a vacuum?

Run the engine and listen for a hiss of air around the brake pedal. If nothing can be heard the brake booster is faulty and needs to be replaced.

Why do the rear brake pads on a Buick Regal, with new calipers, wear out in only three months?

Case Details: The parking brake cable has been correctly adjusted and the ABS harness was disconnected for test purposes but nothing was found wrong.

A common fault, often overlooked, is a defective brake booster master cylinder. What happens is that the cups inside tend to swell, particularly if the wrong brake fluid was ever used. Swollen cups create excessive hydraulic pressure, generally on either front or rear brake lines, and sometimes on both. When this happens the brakes pads are in constant contact with the discs which wear them out prematurely. The solution is to replace the master cylinder, drain out the old brake fluid and refill with fresh fluid of the right type.

As the Buick dealership is unable to supply parts for a 1990 Buick Reatta, where can a replacement brake booster and actuators be found?

Here is a link to a source from where the complete ABS assembly is available.

How to troubleshoot intermittent power brake boost loss on a 1987 Buick Grand National?

The 1987 Grand National used the Powermaster brake system which was known to be problematic regardless of the mileage covered. The earlier model had a far more reliable hydro-boost braking system which is recommended and can be installed on the 1987 GN. Needless to say, that it will need to be installed with all ancillary accessories like the master cylinder, proportioning valve, p/s pump and hoses. Here is a link to a source for a hydro-boost unit.

Why is the brake pedal of a Buick Park Avenue very hard and the dashboard brake light displayed?

A hard brake pedal is a sign of a faulty vacuum brake booster which will have to be replaced. Probably the internal diaphragm has failed in which case the booster will not leak but only lose vacuum assist which accounts for the hard pedal.

Is it safe to drive a Buick with a failed power brake booster to a repair shop?

This is a safety issue which could become progressively worse. If the fluid leaks entirely it could result in total brake failure. The car should definitely not be driven in this condition.

How to troubleshoot a Buick with a brake pedal which is becoming increasingly hard?

This is a red flag for a failing brake booster which needs to be replaced immediately.

From the preceding article it should be clear that the brake booster is the force multiplier which ensures efficient braking especially in a heavy vehicle like a Buick. The booster, and its master cyliner, is also the most susceptible to failure in the braking system. If you have a brake problem and are uncertain whether replacing the brake booster is the right way to go, ask an Expert. Verified Buick Experts provide information and answer all questions on brake booster problems.

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