proportioning valve
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proportioning valve
Okay, after going through my whole brake system and replacing everything possible, I still have a drag when I push the clutch in and the truck could literally stop on it's own if I had enough time to allow it. So I was advised that it may be the proportioning valve that went bad. After a few calls, I found that this is not that easy to replace. Any suggestions? I have never replaced one before and not sure of what I'm looking for. It's a 68 F100, 360, drums all the way around. Oh, and by the way, not a race truck or anything so I'm in no need of something fancy shmancy.
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Well, to be more specific, I don't have a proportioning valve.... it's just a distribution block. So, I'm even more lost now. But the kicker is, when I back up and then go forward, the drag is even worse than just starting out going forward. Any ideas?
Ford Parts Specialist
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From: Simi Valley, CA
C8TZ2B257D .. Brake Differential Proportioning Valve / Obsolete
Fits: 1968/72 F100/250 2WD / 1968/72 F350, all with Manual or Power Drum Brakes / 1967 is not the same.
No Ford Dealer or obsolete parts vendor has any.
These valves get all gummed up inside caused by old dirty brake fluid. Once cleaned, many of them "wake up."
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I need to be even more specific to get a good answer... the following was done about 1 1/2 month ago:
-rear hardware replaced
-rear shoes replaced
-rear cylinders replaced
-driver line to cylinder replaced
started noticing a drag in the rear this past weekend then....
-front hardware replaced
-front shoes replaced
-front cylinders replaced
-passenger drum replaced
-one piece line from block to rubber fitting at diff replaced
-rubber line at diff replaced
-passenger line to cylinder replaced
And as I test drove it, it is still dragging at the rear and a strong pad smell is coming from the rear. But noticed that if I put it in reverse then the drag is worse when I drive forward there after. The only thing I did not do is turn the drums and that's the only thing I can think of. But why would it start doing this after more than a month of daily driving? Any advise?
-rear hardware replaced
-rear shoes replaced
-rear cylinders replaced
-driver line to cylinder replaced
started noticing a drag in the rear this past weekend then....
-front hardware replaced
-front shoes replaced
-front cylinders replaced
-passenger drum replaced
-one piece line from block to rubber fitting at diff replaced
-rubber line at diff replaced
-passenger line to cylinder replaced
And as I test drove it, it is still dragging at the rear and a strong pad smell is coming from the rear. But noticed that if I put it in reverse then the drag is worse when I drive forward there after. The only thing I did not do is turn the drums and that's the only thing I can think of. But why would it start doing this after more than a month of daily driving? Any advise?
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ALL 1967 and later Passenger Cars, F100/350's, Bronco's and Econolines have dual master cylinders and a "Brake Differential Proportioning Valve."
C8TZ2B257D .. Brake Differential Proportioning Valve / Obsolete
Fits: 1968/72 F100/250 2WD / 1968/72 F350, all with Manual or Power Drum Brakes / 1967 is not the same.
No Ford Dealer or obsolete parts vendor has any.
These valves get all gummed up inside caused by old dirty brake fluid. Once cleaned, many of them "wake up."
C8TZ2B257D .. Brake Differential Proportioning Valve / Obsolete
Fits: 1968/72 F100/250 2WD / 1968/72 F350, all with Manual or Power Drum Brakes / 1967 is not the same.
No Ford Dealer or obsolete parts vendor has any.
These valves get all gummed up inside caused by old dirty brake fluid. Once cleaned, many of them "wake up."
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
Below the M/C adjacent to the steering gearbox on some.
Mounted inboard of the left front wheel on the outside of the frame rail on some, some have the valve mounted aft of the left front wheel on the outer frame rail.
You'll have to remove the valve from the truck. Once it's out, then remove the plastic low brake warning light switch. Then use mineral spirits to flush the puppy out.
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Prop. Valve locations:
Below the M/C adjacent to the steering gearbox on some.
Mounted inboard of the left front wheel on the outside of the frame rail on some, some have the valve mounted aft of the left front wheel on the outer frame rail.
You'll have to remove the valve from the truck. Once it's out, then remove the plastic low brake warning light switch. Then use mineral spirits to flush the puppy out.
Below the M/C adjacent to the steering gearbox on some.
Mounted inboard of the left front wheel on the outside of the frame rail on some, some have the valve mounted aft of the left front wheel on the outer frame rail.
You'll have to remove the valve from the truck. Once it's out, then remove the plastic low brake warning light switch. Then use mineral spirits to flush the puppy out.
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From: NW Mississippi
I don't think so. They don't apply pressure, just distribute it. Is it just the rear that is dragging?
-Parking brake not all the way released?
-Parking brake needs adjustment?
-rear drums need adjusting?
-Loose component wedged between pad and drum?
-Parking brake not all the way released?
-Parking brake needs adjustment?
-rear drums need adjusting?
-Loose component wedged between pad and drum?
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Joined: Sep 2009
Posts: 198
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From: Burbank, CA
I'd also take a good look inside the rear drums to make sure the adjuster linkage is installed correctly. I think it's possible to actually assemble it all backwards. The parking brake link and the cable that runs down to the adjuster should be on the rear shoe. The star wheel on the adjuster should be to the rear.
Correct me if I'm wrong, anyone. I'm just going by memory, having recently done the brakes on my '67.
Correct me if I'm wrong, anyone. I'm just going by memory, having recently done the brakes on my '67.
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