68 Base Model Braking Issues.

That distribution block should be pretty common in junkyards if you want to go that route. Maybe look into getting yours rebuilt?

Unless there is a blockage in one of the 3 ports of the primary side of the drum/drum pressure differential valve, I don't see that this would be the problem. All 3 ports of the primary side are common to each other. This means the pressure at all 3 ports would be equal.

But, entertaining the idea it is blocked, any Mustang, Cougar, Maverick, Comet or related Ford/Mercury drum/drum car from '67-up would have a pressure differential valve that would work. The only problem is you don't know if the valve seals in a wrecking yard donor are good when you get it.

There are seals available to rebuild the pressure differential valve.

The following link lists the rebuild parts for a disc/drum valve but, the seals are for the pressure differential valve spool --which is the only moving component inside the drum/drum pressure differential valve body.

https://www.musclecarresearch.com/valve-kit-whead1

https://www.musclecarresearch.com/valve-rebuild-weatherhead-drum

It would also be a good idea to spend the extra $10.00 bucks for the valve lock tool to keep the pressure differential valve from shifting, when you begin to bleed the brakes out.

https://www.musclecarresearch.com/brake-valve-tool

I have one of these pressure differential valve lock tools ...in fact, I just used it recently when I converted my '69 F-100 short bed Ranger from front drums to front discs from a '77 F-100. I also fabricated all the brake lines for this swap.

















Brake warning switch removed from disc/drum combination valve body...



...pressure differential valve lock tool installed to begin the process of bleeding out the brakes.





The valve tool works like a charm and no annoying red brake warning light coming on while bleeding the brakes out.