Hi all

I have searched the forum and cannot find the answer to what is going on with
my 1985 4runner I just bought. When I bought the 4runner the brake pedal would go all the way to the floor. So I thought maybe the brakes just needed bled. I bled the brakes in the right order. Now I have more pedal but it seems once the brakes heat up the pedal goes right back to the floor. I was thinking it is the master cylinder. But I want to get some other opinions before I go and buy one at the stealership.

-AL

 

Have you checked the wheel cylinders for leaks? Sound like a leak in the system somewhere.. Good luck and welcome to YT..

 

Thanks for the reply Bigdady

It appears there is no leaks coming from them but I will check them.

Thanks I had a 87 4runner that I sold. Really liked the truck but wanted
a straight axle. Finally found this 85 that is in really great shape with
109,xxx on it, in stock original condition, including the steel white wheels. Will post some pics soon.

 

Check on the back side of the master for leaks also.

 

Thanks rokblok

Ill check it

 

You had the same problem I had. A new master cylinder from a later model 3.0 V6 Pickup was a nice upgrade and solved my problems.

 

That sounds like a better upgrade. But I would like to stay stock at the moment

 

got my 1" bore aisan oem mc from trail gear.

 

Is the 1" bore bigger than factory, Will it bolt right up?

 

Don't throw parts at it. Check and service the entire braking system and see if something is leaking first. If you can't do it yourself a lot of places do free brake inspections.

Unless you are going large tires over 33, stock braking system is more than adequate.

:wabbit2:

 

yea bolts up.
it's an upgrade, if you go with v6 calipers and or rear discs you will need the newer mc assembly.

 

Thanks everyone for the info

Right now I would like to stay stock. As soon as I can I am going to check out the whole system checking for leaks.

 

Finally got the time to take off the back brake drums on my 4runner.

The back drivers side wheel cylinder is leaking so it appears that is my
problem.

 

update

Replaced both wheel cylinders and new pads. Now I have good pedal
and stopping is alot easier

 

If you get ready to do the upgrade on your front brakes, check out my brake upgrade thread. It is complete with all part numbers and info necessary to upgrade it. As Wabfab stated, it isn't necessary with stock tires, but it damn sure works better. The single best brake improvement is putting a dual diaphram brake booster on it. That will make it stop so much better, and it bolts right up.

 

thanks CAPTDASH

If I upgrade I will check it out