My brakes work great until Tuesday? All of a sudden it seems only the rear brakes are working, or they are working more than the front ?

Any thoughts what to check this weekend ?

Thanks mike

Oh

1985 4runner 4” lift all else is stock. Besides the tires.

also the pedal seems spungy.

 

Master cylinder would be my guess. Upgrade to a 1" master and maybe a dual diaphragm booster from a v6 truck. Does not have to be from a v6 truck though, but when looking for parts at a parts store, it's just makes it easier. I have a master from a t-100 in mine. Cheap at autozone new and comes with the reservoir. Although the 1" AISIN master are the best to use.

 

please explain Upgrade to a 1" ?

 

Aisin 1" bore

 

all you need to know about a booster and master upgrade:

http://home.4x4wire.com/erik/4runner/brakes/

 

any brake fluid leaks?

did the pedal fall to the floor?

Bleed the brakes, or just throw parts at it

 

No leaks, pedal does not go to the floor

 

any difference if you pump the brakes?

no leaks the prop valve, LPSV...

 

nope no leaks. if i pump it the back lock up faster?

 

no, but if your losing pressure from a bad MC pumping the brakes can help..