Brake Proportioning Valve Replacement
Brian Sowle
Tools and Parts Needed
Brass Brake Proportioning Valve

    Part # 25509419 Approx. $60.00

Tools needed:

  • 7/16" Flare Nut Wrench
  • 9/16" Flare Nut Wrench
  • 1/2" Box Wrench
  • Flat Blade Screwdriver
  • 3 cans of Brake Fluid
  • Can of WD-40
First and foremost, spray each of the brake line fitting's with WD-40 a day before you actually start removing the valve. This loosens up all the rust that usually bonds the brake lines to the fittings. The worst thing that can happen is you round the fittings or twist the brake lines, so do the prep work ahead of time.

Step 1

    Jack up vehicle and place a drip pan underneath the proportioning valve area. (inside frame rail on drivers side) When you disconnect the brake lines a lot of brake fluid will drip out.

Step 2

    With your flat blade screwdriver pry the Brake light connector off the top of the proportioning valve. You will not be able to unscrew the top two brake fittings with this connector in place.

Step 3

    A transmission linkage bracket is attached to the side of the proportioning valve. This bracket will have to come off in order to get access to some of the fittings. With your 1/2" box wrench unscrew the two bolts that hold the valve to the frame. After removing the 2 bolts you will be able to disassemble the transmission linkage. Be careful not to loose the linkage spring, washer and plastic ball joint. Now insert 1 bolt back into the proportioning valve and reattach it to the frame. This makes it easier to loosen the brake fittings.

Step 4

    Now loosen all the brake fittings. There are (3) 7/16" fittings and (2) 9/16" fittings. If you have trouble with 1 or more fittings spray some more WD-40 on it and wait a half hour or so. Take your time here or you will be spending more money and time replacing the brake lines!! Once all the fittings are disconnected, remove the 1/2" bolt and remove the valve.

Step 5

    Take the new BRASS proportioning valve and thread the top two brake fittings into the new valve before attaching the valve to the frame. Be careful not to cross thread any of the fittings!!! Believe me this will save you time later on. Now thread the remaining fittings into their respective holes. Do not tighten down any of the fittings yet!! Take your 1/2" bolt and reattach the valve to the frame. Now tighten all the fittings. Reattach the transmission linkage bracket and screw in the (2) 1/2" bolts. Reattach the Brake light connector.

Step 6

    Now comes the fun part, BLEEDING THE BRAKES. Please refer to Ken Mosher's BRAKE DANCING article for proper bleeding procedures. Total time should be about 1 to 2 hours including bleeding.

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