dikatry

Hello,
(Sorry for the spelling..it doesnt let you edit titles)
I am having some problems with my 91 4Runner 4wd 3.0. I bought the rig about two years ago and have had several issues with it, including an engine swap. For some reason I feel bonded to it now and keep putting money into it. I currently have OME and Billstein shocks on the front and rear. Nothing else aftermarket.
About 2 years ago, right after I got it I had new brake pads put on and the rotors turned. Pretty quickly after getting it back from the mechanic , I would be driving and it would feel like the wheels would seize up. Sometimes it would be worse than others, and sometimes it would be longer than others. One time it took me from 60mph down to stop. Another time it stopped me on a hill. This tool place over the course of about a week. On my way to my mechanic to have him look at it, it fell like whatever was grabbing just gave out. Since then the brakes are very week. I can push them to the floor going 15 mph and come to a rolling stop. I have had my mech look at it twice, and I have taken it to two different Les Schwab locations, everyone says they can find nothing wrong with it.
I also have been having some problems with the steering and am wondering if it could be related to the problem with my brakes. Last spring, the valve on the power steering pump started sucking ps fluid into the intake manifold. Once again, no one could figure out what was going on because there was no leak, I had to come on yotatech to find the answer. Well, I have since replaced the valve, but the pump still squeels when I first start up my 4Runner. Also, if I push on my brakes when I first start up the power steering pump squeels louder. My steering is very very loose. I live in a windy and icy area, and driving on the highway can be interesting. I also like to camp and hunt, and driving on forest roads with this thing is hard on the body, it bounces all over the place.
Can anyone provide any insight? I did some research and found a post with a similar problem to mine, but no solutions addressing the brakes. I am planning on replacing the control arm bushings, ball joints, Pitman arm, idler arm, and the inner and outer tie rod ends.

dikatry

bump please, sorry for the misspelling

snoweater

I'm not very experienced in auto repair, but i've been having a similar problem to yours. After i moved from the east coast to CO, while towing a heavy trailer, i've had locking brake issues as well. I've heard 4runners are notorious for warping brake rotors, so that's what i thought it was. Took it in, everything looked fine including the rotors, had them bleed and test, said they couldn't find anything wrong! rotors couldn't be machined, too thin already, but he said they didn't need it.
Problem persists. Basically, when i'm going pretty slow (under 20mph) and lightly braking, the front right tire locks. Only the front right, and it definitely locks up! If i come to a stop at a light, when the road is snowy and it's cold out, I have to throw into reverse briefly to get the thing to unlock, otherwise I basically do a donut on my front right tire.
I'm going to replace the pads and rotors this week, so i'll let you know if that fixes it or not! I'm 90% sure it will, can't think of what else it could be...and the rotors are old anyway.

As for the steering on yours, it's probably unrelated to the brake issue. I recently replaced the tie-rod assemblies (whole thing), steering stabilizer, rebuilt the idler arm with new bushings, and replaced front shocks ($400 in parts) on my '94 runner and it drives way better. Pretty easy to do, just get an alignment after the tie-rods.

JigsN Rigs

Sounds like your getting uneven pressures to your wheels. Does your brake light pop on sometimes when your breaking.. I had something similar happen on my jeep and it was the brake booster. Not the MC like I first thought. Do you get pessure when you pump the brakes?

TRDPARTS4U

I'd check the front calipers first, make sure they're releasing, check for corrosion and make sure tha pads are not binding on the pins. A malfunction on the master cylinder can also cause the front brakes to lock up, but I don't know how to test that. Maybe someone else will chime in.

Thanks,
Gerone
866-233-4305

JigsN Rigs

Correct me if I'm wrong but I don't think the MC will make just one wheel lock up.. You can check calipers but I would say they are probably fine.

TRDPARTS4U

That might be, when my Tacoma's brakes hosed up the fronts locked up then would not release and it was the MC.

Thanks,
Gerone

snoweater

Never had a brake light come on in mine. looked at the calipers, seemed to release/engage smooth to me. had the shop look at them too, said the same thing.

The fact that my problem started after towing a heavy trailer on highways etc for 2000 miles makes me sure its a warped rotor, but not sure why the passenger would warp and not the other...only thing i can think is i maybe hit a puddle, ice, snow or something on the passenger side when it was hot and warped it. but really have no clue...i'll know soon after i do the rotors/pads hopefully!