anti lock brakes on 95 riviera

[Guest sintid58]

My daughters 95 Riv anti lock brake light is on and I had it looked at by a mechanic. He told me I would need to replace the entire front hub on both sides to repair this. They said the sensors are bad. Can the sensors be cleaned or does anyone know if you can just replace the sensors Thanks

[NTX5467]

During that general production time frame, the wheel speed sensors for the anti-lock brakes were an integral part of the wheel bearing hub assemblies. There is a very close spatial relationship between the magnet and the tone wheel in the hub from which the wheel speed sensor derives the wheel speed signal that goes to the anti-lock brake computer. What might also be investigated is to make sure the wiring connections from the sensors to the body wiring harness are clean and make solid contact. Similarly, the condition of the wires themselves could be an issue.

Hopefully, the mechanic pulled the codes from the brake system computer to deterimine the light was on due to codes relating to wheel speed sensors and didn't just guess. I know that we sell some of these every so often, but usually just one at a time.

Typically these might be dealer-only items, but I saw in GM High Tech Peformance magazine where they got some for a Firebird at a local auto supply, made by TRW. I suspect they also might be available from NAPA too.

If the brake computer does not receive wheel speed signals from the individual wheels, it will prevent the anti-lock from working plus probably the Traction Control might not work either as they work from the same sensors.

Your mechanic might be reputable, but my main concern would be that a full and thorough diagnosis was performed to determine that the wheel speed sensor was what was setting the paraticular code instead of just guessing.

Enjoy!

NTX5467

[Guest Shaffer]

Be glad it is not the modulator. Someone on the stationwagon club has a 96 Buick Roadmaster Estate wagon that the modulator went out on. Replacement was estimated @ $1400. Another lady with a 92 Caprice had the same problem- same estimate. Luckily, the ABS on my 92 Park Avenue, 95 Concorde and 94 Lumina are CURRENTLY working fine. At these prices, I hope that nothing happens to them. Good luck.

[Rawja]

Reattas have weird and expensive first generation Teves ABS braking systems that are prone to failure. A resource we have come to trust for rebuilt Master Cylinder/ Valveblocks/Accumulators is Prior Remanufacturing www.priorreman.com their selection and quality is outstanding and their pricing is excellent. I would advise anyone who is looking into getting the "head-end" of their brakes done to check them out.

[NTX5467]

I'd forgotten about the Teves system on those cars. It seemed like GM was playing musical chairs with which ABS system went on which car back then. It's one thing to spread the business around, but it didn't help too much on the repair side of things.

The ABS module for current GM light trucks is about $800.00. When it goes out, the complaint is a "running motor under the vehicle" or similar and the ABS light being on. They have a neat "self-bleed" mode that is activated with the GM Tech2 scan tool. Pretty neat and quick. Trying to manual bleed the brake system on these light truck vehicles never seems to get the pedal to feel right, but it acts right when you drive it (as we found out after a couple of gallons of brake fluid).

Any time you deal with an ABS system, you need to know the exact model year (from the VIN and not the safety inspection sticker or build date) and model of the vehicle. The model of the vehicle for the particular brake system it has and the model year as there were updated versions each year too.

Probably the worst brake system we had to deal with is the older PowerMaster system on the middle '80s GM full size wagons. It had some unique (i.e., wierd!) operating characteristics (as in partially emptying the brake fluid from the master cylinder during operation) too. The principle for a small, self-contained booster that didn't require engine power to run is good, but it just didn't work out back then. This was during the time that full size GM wagons had the "low power" Olds 307 V-8 that probably didn't have enough vacuum to run the brake system, not to mention the Turbo cars too.

While they were in production, we could get them new. "New" dried up and then it was strictly "reman" from GM. Then when that deal dried up, it was necessary to call some lawyer's office to get one ordered. Then that stopped too. Salvage yards were empty by that time too.

Enjoy!

NTX5467

[GMPARTSMAN]

HEY NTX5467, AS A RUNNER-UP, HOW ABOUT THE BOOSTER/MASTER CYLINDER COMBINATION

ON THE LATE 80'S W BODIES, NO SERVICE PARTS AVAILABLE FOR THE MASTER CYLINDER, JUST A ALMOST TWO THOUSAND DOLLAR ASSEMBLY.