Does a proportioning valve work for either power or manual brakes or are they specific to power or manual setups? I want to use my valve from a 1974 F100 with power brakes on my 1964 F100 with manual brakes. Will it work? Thank you for any information that you can give.

 

it will only work if you are upgrading to disc brakes in the front. on 61-66 and prior all had drum brakes wich reqiures the same amount of force to all four wheels. disc brakes take most of the stoping action so thats were your P/P comes in. i am not sure if there is a easy upgrade for disc brakes proir to 65. others will chime in.

 

If you're using the Ford prop valve for a disc brake conversion, it doesn't matter if it's power or manual. The valve is the same AFAIK. I used a power brake donor on my manual brake truck with no problems.

 

That is not correct.

Ford went to dual master cylinders in 1967 on all the cars, Bronco's, Econolines and F100/350's.

All these vehicles had a proportioning valve installed, whether front disc brakes were present or not.

If the vehicle has a dual master cylinder, it uses a proportioning valve.

The valves used for drum/drum applications are not the same for disc/drum.

The valves may be specific for a certain model, they may not be. It depends on the application and the GVWR.

As ddavid pointed out, Power or manual brakes makes no difference.

4 brake lines screw into the valve. There is another threaded hole for the low brake fluid warning light switch.

If you are using a valve on years prior to 1967, there will be no warning light on the dash, so the hole must be plugged. You can get the switch and use that for a plug.

1973 was the first year for front discs on F100's. 1973/79 F100's: Manual disc brakes were standard equipment, power disc brakes were optional.

F250/350's offered (optional) power (only) disc brakes beginning in 1968, became standard equipment in 1973.
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Voodoo66: As Original: D3TZ2B257A .. Disc Brake Proportioning Valve / OBSOLETE / Fits: 1973/74 F100 / 1973/74 F250 w/a 6200 lb. GVWR.

No Ford dealer or obsolete seller has this particular valve. Proportioning valves are available from aftermarket suppliers.

 

Hate to disagree, but I had a '71 donor truck that obviously had the dual M/C and it had only a distribution valve, which is not a proportioning valve. The only function a distribution valve has, in case of brake line failure (massive leak), a pin will slide to the leak side and effectively shut that side down(and turn "brake" light on), so you still have some limited brake power. A proportioning valve will do the same thing, but also limits the max pressure to the rear brakes.

 

You can disagree if you like, but this is what Ford sez in the 1964/72 Ford Truck Parts Catalog / Text / Section 22 / Page 32:

2B257 Valve - Brake Pressure Differential Proportioning

C8TZ2B257D

Fits: 1968/72 F100/250 2WD & F350 / Use with split hydraulic brakes.
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Text: Section 22 / Page 33.

2B264 Switch - Brake Pressure Differential Proportioning Valve Warning Light

C8AZ2B264A

Fits: 1968/72 E100/350 / F100/350 / P350/500 (also fits 1973/79: F100/350; E100/350 / 1973/75 P350/500.)

It could be a matter of semantics, but I've never heard of a proportioning valve refered to as a distribution valve and Ford has no listing for a distribution valve in the truck parts catalog.

And the parts catalog is all I have to go by.

The cars from 1967/69 used two valves, one * was mounted on the rear axle.

Example: 1967 LTD: C7AZ 2B257C . BPDPV & C7AZ2B091A .. Front Disc Brake Pressure Control Valve *

 

Semantics it may well be, but calling what I have a Differential Proportioning Valve is a complete misnomer.

FWIW: I am running said non-proportioning "valve" on my '65 with power disc brakes and have no issues until you approach maximum, "emergency" braking...without the differential proportioning device they will lock up.
To do it right, I should have a proper proportioning valve in there.....

 

I agree with Prostock, Never heard it called a distribution valve but I have been told of the difference between the "proportioning valve" from early vs late years. And I think thats my problem. I have the light and very limited brake power on my 75.

P.S. Disc brakes were not a standard for f250's in 73 but in 76.

 

ALL 1973/79 F250 2WD's came standard with power front disc brakes.

The ONLY F250's that came with front drum brakes were 1973/75 4WD's.

1976 was the FIRST year 4WD's came with power disc brakes.

The same applies to 1973/75 F100/150's with 4WD.

 

Mine is a '75 F250 4x4, drum fronts. They have been locking up because when I got this truck the front brakes were dry. So, as you may have guessed, the valve has pushed toward the front lines to block them off. Problem is I can get the front drums to work ok for stopping, but the bias is to the rear (and will lock em right up) and because of the valve being stuck they wont bleed off excess pressure, so the fronts drag.

The whole semantics thing has me confused. So which valve does my all stock truck have in it?