Has anyone converted a 4 drum highboy to a power disc brake front axle? If so, what did you use for the power brake booster, the master cylinder, and the prop. valve?

 

When you go to Napa (or your parts house of choice) order the brake components for a '76-'79 F250, they won't have the proportioning valve though, you can buy that at JBG for 60 bucks.

 

I wouldnt waste the money on that axle. I would at least find a open knuckle lp d44 w/ disc thats complete. Then all you need is the booster and the proprtioning valve. You at least get to do away with the leaky knuckles.

 

By "converting" i was assuming that he meant "swapping" in the above mentioned axle (or a 78/79 hp d44), but you never know...

 

Yes, that's what I did. Bought a 1979 Dana 44 with disc brakes. I also bought the power steering box and pump. The brakes are really bad (spongy) even after proper bleeding. Has anyone tried one of the adjustable prop. valves?

 

Oops I misread op was asking. I'm steering him in the wrong direction with a lp44. A 78/79 Hp 44 with the power steering would be a great swap if that's what he wants. I skipped that step and went right to the D60 and power steering swap that I'm still working on.

 

Did you use the prop valve from the donor truck?

 

No, it still has the original 1974 prop valve from the 4 drum brake system. I did not buy a donor truck, only the parts so no access to a 79 prop valve. I noticed adjustable ones for sale in Summit and Jegs and wondered if they will work??? Maybe easier to find a used 79 from an F250?

 

The 4 wheel drum prop valve is more of a "distribution block", it doesn't have the bleeder valve for disc brakes, so as a result the front discs can't be bled properly.

JBG sells this one for $59 Aftermarket Pro Valve

 

Just like montana_highboy said...it's basically a distribution block...i just went with a stock proportioning valve when I put a 76 Disc axle in my 73 Highboy...it works great...and was only 5 bucks at the u pull it yard...I didn't want to mess with having to get it all adjusted with an adjustable one anyway.