hard right pull during braking

[jones]

84 K10 w/14bff/D44.drives staight and can even take my hands off the wheel and no problems.But hang on when you hit the brakes.It's crazy.I was checking it out and found my front axel shaft u-joints were toast(changed them),brake fluid is full,caliper pins were a bit gummed up(cleaned them w/ a wire wheel and coated w/ anti-seize)calipers looked good w/ no abnormal wear on either of the pads,rotors are in looking good(no grooves or pitting,though they are kinda glazes looking),shock mounts in good shape,sway bar bushings have seen better days as well as the steering stabilizer,no rear brakes even though all hardware was new when I swapped to 3/4t. axels 5 years ago,no leaking wheel cylinders(at least on the outside.brake pedal seems mushy and the brake light comes on every once in awhile but goes back off in short time.

Am I overlooking something?

 

[K10 KRAWLER]

You could have a seized caliper, one way to check would be to jack up the truck and have someone else press on the brakes, try to turn each wheel with a pry bar, or even pull off the calipers and see if you can push then back in with a c clamp

 

[toomany]

Caliper, pins or the line of that caliper are most likely bad. Even though the calipers look good, the bushings could be slopped out. Binding up when you hit the breaks. Or the piston could be getting stuck in the bore.

 

[andyblack]

I once had the piston inside its caliper seize up due to corrosion on the outside of the piston. The truck was pulling real bad to one side, then it got to where it would barely stop. I took the caliper loose and had someone step on the brakes until the piston popped out of the cylinder. Then I shined it up with a Scotch Brite pad, used a c-clamp to put it back in and it worked fine.

Also, do you have steel brake lines or rubber ones?

 

[loafer]

I've had numerous calipers seize on me, though part of that may be due the massive amount of salt they put on roads up here.

An easy way to tell is to see how hot the hub and wheel are after you drive a few miles. Last time one seized on me the hub was so hot I pored water over it to cool it and it boiled the water

 

[andyblack]

Yeah that's about how mine was. I could smell it burning and feel the heat when I just put my hand close to it. That truck had been sitting up a while when I bought it, I think. That could be why it was so corroded.

Also if your rig has had an underwater excursion and sat in the water a while, the moisture that sits in the bottom of the cylinder can cause the bottom of the piston to corrode and get all rough.

 

[hack]

Sounds like you need to do a standard brake job (turn rotors and new pads) i had this same problem, new rotors (mine could not be turned) and new pads works perfect!

 

[jms]

If a caliper were dragging, the truck should pull to the side all the time, not just while stepping on the brake?
The brake warning light coming on would suggest you have a low pressure situation somewhere - air somewhere in the system / leak / internal leak @ master.

 

[andyblack]

Won't a low brake fluid level cause the brake warning light to come on sometimes? Mine has never come on before.

 

[jones]

I'll do some more checking. The pads are new as of last spring and aren't even showing wear.The truck has only been around the yard and pulling people out of snow drifts.But the salt on the roads could be causing problems with the calipers. I'll get my wife to hit the brakes when it's jacked and see what happens.I've never smelled anything getting hot,which means nothing I guess.

I'll let ya know what i find.Thanks

 

[89yimmiJ]

There is a special tool available to rent at some auto parts stores/ mechanics. It is basically a metal block that you put into each caliper to measure caliper pressure. It has a hose with a gauge attached and it tells you if your calipers are producing enough pressure ou unequal amounts of pressure.

I had one on my truck that worked, was not seized and yet still pulled a little. Used the tool and found out that one was not producing enough pressure. Swapped calipers and problem solved.