strange braking issues

[theMANry]

hey guys can you help me out.

my uncle has an 01 taco, 4wheel drive, 2.7 auto. its having a realy weird problem that i cant figure out.

sometimes when you drive it the pedal gets really hard and you can feel the brakes dragging.
right when this happens ill jack it up and the tires, both front and rear, are locked in place and i cannot spin them by hand. but if we wait an hour they will spin with no problems. it seems to have more of a problem after being taken down a rough road.


any ideas?

[humanoid]

Stuck pistons on the calipers maybe? Do you know when the last time the brake fluid has been flushed?

[hilux5084]

My guess is the master cylinder next time it locks jack up a wheel to check and loosen the corresponding fitting on the master cylinder if the pressure is instantly relieved and the wheel turns freely now you need a master cylinder.

Joe

[theMANry]

Originally Posted by hilux5084

My guess is the master cylinder next time it locks jack up a wheel to check and loosen the corresponding fitting on the master cylinder if the pressure is instantly relieved and the wheel turns freely now you need a master cylinder.

Joe

i was thinking the same thing but its all 4 tires that have dragging brakes. this makes me think it could be the booster applying slight pressure, but that would not explain the hard pedal and i would think that it would be a constant problem, not intermittent.

[wideawake]

Rough road...hmmmm......Load compensator getting hung up maybe?

Fluid flush is something I would do soon, could be a flake of rust getting hung up and acting as valve, thus keeping pressure in system.

Brake fluid is hydroscopic/hygroscopic-(depends on your definition), which means absorbs water, meaning that brake fluid can become very corrosive to metals!

[theMANry]

im going to go grab a container of new brake fluid and flush it tomorrow. im really leaning twards the rust flake or dirt issue because the pedal free height, free play and reserve are all in spec.