At my wit's end

[toddtheodd]

Ok,
1972, c10, lwb, 355, front disc brakes.

I've replaced:
Master Cylinder
Front Brake Hoses (both sides)
Calipers (both sides)
Rotors (both sides)
Pads (both sides)
and inner and outer bearings (both sides)
Flushed the brake fluid

My front right wheel is dragging. If I lift the truck up, and spin the wheel, it stops spinning again immediately. Not after spinning a couple of revolutions, but after a couple of inches.

WTF could it be? I've replaced everything, except the proportioning valve, but I don't think the proportioning valve would cause only the front right tire to drag. The front left tire is fine, but the front right is dragging.

[Sinister]

How did you adjust the wheel bearings? If you pull the caliper does it spin freely?

[BIG ORANGE]

Make sure you didnt over tighten the castle nut on the spindle 1st.
2nd just because you replaced the parts doesnt mean the new parts are good
I've worked for a Auto Parts store for the last 9 yrs and I see new or reman parts sold from time to time and they be defective.
You could go back and blead your brakes again if thats the problem area!
Good luck.........

[Andy4639]

Check the castle nut on your spindales make sure it's not over tightened.

[Alex Hayley]

If you have determined that the dragging is not in the hub, get another caliper. I just went through the same issue. It turned out to be a defective caliper.

[cdowns]

have you adjusted the pushrod for the proper pedal freeplay

[toddtheodd]

I am going to check the caliper bolts. What ft/lbs should they be?
When the caliper is off, the rotor spins freely.

[71 super]

Replace the caliper again. The piston is not retracting, the pins will not cause this to happen.

[toddtheodd]

Well ****... *sigh*
OK, I'll replace the caliper... again... and check back in after that.

[toddtheodd]

Well ****... *sigh*
OK, I'll replace the caliper... again... and check back in after that.

[oldblue1968chevy]

have you converted to power brakes lately? i had an extra gromit between booster/mc

and my brakes still hang a lil i think its the adj. rod

[SweetandLong68]

Definitely sounds like a dragging caliper to me! Would check that out.

[oldblue1968chevy]

yeah, but WHAT would cause the caliper to drag (unless plain faulty)...

[CHEMPOWR]

Ensure you didn't kink the brake hose by spinning the caliper 360 degrees before remounting. I did that when I was learning to work on cars years back and it made that caliper stick.

Just another thought.....

Good luck

Originally Posted by oldblue1968chevy

yeah, but WHAT would cause the caliper to drag (unless plain faulty)...

[SweetandLong68]

Originally Posted by oldblue1968chevy

yeah, but WHAT would cause the caliper to drag (unless plain faulty)...

These are all good ideas on causes... The bleeders on the calipers should be pointing up. Are they? It is possible to have the calipers on the wrong sides of the truck....Just something to check.

Other than that...bent or seized up slides but most common is just a junk caliper. See if it will compress in...

lata
CHRIS

[raycow]

What if the pins were bent? This could cause the caliper to be cocked relative to the rotor, and it would definitely bind then.

Ray

[toddtheodd]

Ok... tomorrow I pick up another caliper to replace the one that is "bad".

A few things though that were brought up:
-They are power brakes, factory installed
-Yes, the piston will compress (with a c-clamp), but as soon as I press the brakes, they drag again.
-The bleed screws are on the top
-The brake hoses are new, and so are not twisted
-I actually have too much freeplay in the brake pedal, besides, that wouldn't cause just one wheel to drag

After I replace this caliper, again, it will be #3 on that side. I just find it kind of odd that the old caliper, and the new caliper, were both dragging. I mean seriously, what are the odds?

Luckily it is covered by warranty, so it will only cost me some time to switch it out, and not money.

[SweetandLong68]

Man that is weird.... What about the non rubber part of the line... Is there a kink or something going on there? Maybe something inside the line itself?? All odd things but this situation is an odd one!

lata
CHRIS

[trusty72]

yeah ive seen a rubber line have a bad spot on the inside causing a check valve effect doing the same thing u described.

[toddtheodd]

Yeah... but 2 rubber lines in a row? Highly unlikely.

[SweetandLong68]

True.... But there are only just so many parts in a brake system. I am still thinking a caliper.

[Paul M]

if you didnt change the rotor on that side(possibly the bearing race wasnt seated all the way and holding the rotor out of center in the caliper)..and all you did is go from the old caliper to the new,id say once the old new caliper is off,disconnect the hard line from the Y block where it goes to the other front side,spray some brake cleaner in there and blow the hard line out with compressed air. could have some rot/flaking in the hard line thats acting like a one way valve, letting in pressure but not releasing it. if worse comes to worse, rig up a whole new hard line to test the theory.

[54Caddy]

I have the same problem on my 79 and i also have all new parts, i decided to change the proportioning valve and still no luck im stumped just like you man good luck its a headache.

[SCOTI]

Try swapping all the parts side to side & see if the problem remains on that side or follows the parts.

[Rat Bastid]

good idea scot