I have a '70 2WD SB F100, originally with manual (drum) brakes.

Installing master cyl and booster from a '78 F150 2WD into the '70. Is the proportioning valve located in the same place in those two trucks? I'm wondering if prebent brake lines -- master cyl to prop valve -- for a '78 F150 will fit in the '70 with the '78 master cyl and booster.

 

The 70 (actually a distribution block) is mounted inside the frame rail while the 78 is mounted to a bracket bolted to the steering box.

 

D5TZ-2B257-B .. Brake Differential Proportioning Valve / Marked: D5TA-2B524-FA or FB / Obsolete

1975/79 F100/150 2WD/4WD / 1975/79 E100/150 / 1975/79 F250 2WD with single piston caliper disc brakes / 1978/79 Bronco & F250 4WD / 1979 F350 4WD.

Based on pics in parts catalogs, location varies depending on vehicle. Bronco & F100/150 4WD: Bolted to a bracket, located on the inside of the left frame rail.

E100/150 & F100/150 2WD, F250 2WD, F250/350 4WD: Bolted to a bracket and located on the inside or outside of the left frame rail, inboard of the left front wheel, or slightly to the rear of it.

 

Thanks. Not the answer I was hoping for but now I know. Guess I'll have to do some bending and try some double flaring.

 

You have the valve, so I assume you removed it from a donor truck. Where was it located? Did you take pics before you removed it?

When swapping parts, a camera is your best friend.

 

Didn't take the proportioning valve or I would know where it was. I might be getting senile but not that bad yet.

If a proportioning valve is required I'll get a variable one.

Pre-bent lines were an after thought -- after I thought some more about tube bending, double flares and availability of '78 lines for $30.

 

Put it where ever you want, really doesn't matter. Buy prebent or make your own. Not aware of anything being cast in stone.


John

 

All FoMoCo vehicles with dual master cylinders (introduced in 1967) have what FoMoCo calls: Brake Pressure Differential Valve.