These are the prop valves I found under my 95 park avenue ultra. I suspect one might have gone bad as one drum only gets 1/3 the pressure as the other drum. Modern replacements look nothing like the ones I have. Can someone identify this part?

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Home >> Buick >> 1995 >> Park Avenue V6-3.8L VIN K >> Repair and Diagnosis >> Brakes and Traction Control >> Hydraulic System >> Brake Proportioning/Combination Valve >> Description and Operation >> Combination Valve >> Combination Valve

Combination Valve

Fig. 5 Combination Valve:

DESCRIPTION
The combination valve, Fig. 5 is a metering valve, failure warning switch, and a proportioner in one assembly and is used on disc brake applications.

OPERATION
The metering valve delays front disc braking until the rear drum brake shoes contact the drum. The failure warning switch is actuated in event of front or rear brake system failure, in turn activating a dash warning lamp. The proportioner balances front to rear braking action during rapid deceleration.
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Hi! Thanks for sharing the service manuals.

In my car the master cylinder has only 2 outlets, that immediately enter the abs pump. From there it has 4 exits, one for each wheel.

The only proportioning valves I found are the ones at the rear of the car, for the rear brakes. And are not connected directly into the master cylinder...

I got the pressure tested and one of the lines is 50 bar and the other 100... I will keep looking but your link is amazingly helpful.

Cheers

Once again, thanks for sending that link. I could find the part number 25640216 and seems to be a direct fit.

The alternative is part number 19244448 but I am unsure of the size and general dimensions.

Cheers and regards from Spain