I tried a caliper rebuild (seals only), no improvement. The right side goes through pads much faster than the left side, which seems weird 'cause it's pulling to the left (right side not working as hard). I have heard the flex hose on the right side could be swelling, causing uneven pressure. Anyone have any ideas?

 

Are the pads wearing evenly? Or is one pad wearing faster than the other on the same side? Make sure the sliders aren't seized.

I think you are on the right track with the brake hose thing, it could be swelling, or if the caliper ever hung from the hose it could be deformed and restricted inside causing low pressure on that side. It could also be something complicated like a bad proportioning valve.

Also check the back brakes out, make sure they are working right and adjusted properly because they can cause a pull also.

-Jon

 

If a brake hose is swelling then it's probably the other side as your right side seems to get more pressure.

Check your wheel bearings on 2wd and have your hubs inspected on 4x4. Could be worn-out hub (bearing inside) causing brake rotor to move around. 4x4 hubs are sealed and not repairable.

If it's not a bearing thing or warped rotor try new caliper. Did you get the rotors turned or replaced with new pads? Could have glazed the pads on right side (less braking on that side).

 

If your right caliper is hanging up and clamping more than the left, it will pull to the left upon initial brake application since the right side will be warm/hot and the left will be cool.

If the right side is not unusually-tight (jack the front end up and rotate the tires. If you can 'one-arm' the tire, it is not dragging excessively), and if the left side is unusually loose (two-finger rotation of the tire), then check to see if you have excessive bearing wobble on the left wheel.

The calipers rely on some lateral runnout of the rotor to aid in loosening the pads against the rotor -- and if/when there is excessive wobble, the pads in the caliper of the 'less-wobbly' rotor/wheel will be looser than those of the 'true' rotor/wheel.

Be sure to ensure that the caliper slides/guides are free of rust; and that they allow the caliper to move as freely as possible.

If your truck is old enough for the caliper pistons to have become pitted and/or their o-ring seals have become sticky, then you may be experiencing some hysteresis which prevents the piston from being pulled back into the bore by the seal (it's very small, but real).

A mushy hose is unlikely to be the culprit, since the pressure is so great as to pretty evenly divide-out between the left/right in all but a very unique situation (not discussed here).

Lastly, it is assumed that the rotor condition is equally smooth on all four surfaces -- and there is no 'rotor pulsing' from rotors in need of machine work.

Please post your results.

 

Thanks for the wheel bearing tip, haven't checked that yet. Was busy doing thermostat/housing /upper hose replacement. I think the right piston is binding a little. I noticed when pushing it back in with the c-clamp that it was resisting all the way when compared to the left. Question now is do I replace the piston only or the whole caliper? They both looked very clean. Thanks

 

The normal repair in this situation would be a rebuild of both calipers -- primarily to ensure they balance with each other.

If you don't do it yourself, simply exchange the calipers for remanufactured ones.

[edited] I just re-read your original post, so I guess rebuilding by yourself is the plan. Did you use a cylinder hone? If the pistons are not pitted, and the cylinders were honed, I'm surprized that you still have trouble (back to the other suggestions I gave). If you didn't hone the cylinders -- or if either the pistons or the cylinders were pitted/rough, then re-evaluate the exchange option.