I'm having a rather frustrating issue. The problem first began about a month or 2 ago and I've been trying to narrow it down with no luck. The problem is while I've driving my brakes seem to apply themselves. The front drivers side is the one that I notice doing it the most. The rear drivers side drum seem so heat up but doesn't seem to get as bad as the front. Its a fight to get the car going. My cars a 5spd and I don't even need to press the brake when its happening because the truck stops itself pretty quick. While its happening I've also noticed the front shakes quite a bit and the pedal gets alot firmer. I've pulled the ABS fuse to disable the ABS in an attempt to rule that out and I have. The fuse is pulled and it still does it so I'm sure its not the ABS. I'm now leaning towards either the brake master cylinder or the front calipers. I'm more leaning towards the master because the issue isn't always present. When the brakes release they function fine and everything is great. Has anyone else had this issue?

1996 4Runner SR5 4x4

 

have you tried to just change the fluid. wont cost as much as the master but reading it does sound like the master is not releasing when they heat up and the fluid expands.

 

Hmm you mentioned your rear brakes are acting up? have you checked underneath the truck and check your E-brake cables and what not?

 

There may be water in your brake fluid, this can cause the calipers to apply but not release. Brake fluid is hygroscopic, which means it absorbs moisture and if you've never had the fluid changed or the reservoir cap is bad you may have a good bit of moisture in the system. I would start by flushing the system with several quarts of quality brake fluid.

 

I'll try flushing the system and see if that does anything, I beleive it was flushed when the rear seals and bearings were replaced back in aug. Its worth a shot though. As for the rear brake problem. I've looked over the e-brake cables and levers and there pretty free. I use the e-brake on a daily basis being that I have a 5spd. I haven't noticed any sticking in the e-brake.

 

+1 with tunnelmotor.

You also make want to make sure the sliding pins are not stuck. Check all the hardware around the front calipers is working so your rear brakes don't have to do all the work....

 

I can think of 3 possibilities:
Contaminated brake fluid; could be water, also if anything other than brakefluid has been added, it can cause all of the rubber parts of a brake system to swell up, ie seals, brake lines etc..

An out of adjustment brake pedal or brake booster rod

Finally if the brake shoes became oil soaked by the leaking axle seals and were not replaced with the seals, they may be sticking to the drums when you release the ebrake.

From reading you're description, I would lean towards the 3rd option. Make sure you're brake shoes were replaced. Even if they were, if the drums were not cleaned and turned the new shoes may have become contaminated.

 

I just wanted to update the thread and say that i got the problem solved. After having me puzzeled for a few weeks and not wanting to throw parts at the issue or freeze working on the truck outside, I got it solve. I was right when i guessed at the brake master cylinder. Its been changed and for the last 2 days not issues. Trucks back to running smooth and hopefully my gas mileage goes back up! Thanks for all your input.