Last fall, as many of you remember, I attended the huge swap meet held in Carlisle, Pennsylvania. One of the major companies specializing in brake-related items had a brass brake proportioning valve on display. I knew that it looked either exact or darn close to what was used on our Turbo Regals, so I bought one. I sent it off to Richard Clark to run some pressure checks on it and to install it on one of his cars that he drives. I knew from the application that it was for a front disc brake setup with rear drum brakes in the rear. Richard recently reported his findings… after two months of testing, it performs like it should.
All the fittings were exactly correct and it was a direct fit.
What some of you may not realize is, back when the cars were new, GM used 4 different suppliers for this part. It was not uncommon for GM to use several different suppliers, but I think this was unusual to have 4 different suppliers. The manufacturers were Bendix, Delco, Kelsey, and Weatherhead.
This is not a part that would normally fail, but the problem is, only the Weatherhead brand was all-brass construction. The other 3 I mentioned above were not, and as a result they turn to rust! The next time your pride and joy is on a lift, check it out as rust can spell problems down the road, as you can imagine.
This brake proportioning valve sits under the driver’s floor pan, approximately where the floor starts to curve upward. It’s about the size of your closed fist.
You will see it, since the brake lines go to it. Having had several GNXs, we have seen first hand that some of them received the ones that turn to rust. With just
1 out of 4 suppliers manufacturing the valve in brass, the odds are against your car having a brass one.
You may have been lucky to receive yours when Weatherhead was the main supplier. This proportioning valve fits all 1982 thru 1987 Regals V6 and Turbo V6 models.
No matter how careful you are with your car, because of its location, if it’s not made in brass, it probably has turned to rust by now. As for confirming my facts, in my Buick library collection I have a fairly rare Buick booklet entitled “Parts Identification and Inspection Guide.” It has a Turbo logo on it. It shows the various parts for our cars and how to decode the system they used on the date code that was put on the various parts. It is a pretty rare booklet, since I have never seen another one for sale. The booklet listed the
4 suppliers we mentioned for the brake proportioning valve.
Going by memory, there may have been a Service Bulletin of some sort concerning the brake proportioning valve and the rust issue. But, to my knowledge, there never was an actual recall like GM had on the brake switch.
GM discontinued the brake proportioning valve about a year ago.
With the knowledge we have today, we know the Turbo Regals had brake problems in almost every area; the brake bowl, the brake switch, and the proportioning valves.