Patrick1976

Here's my problem. I've owned my '86 4runner for about 4 years now and ever since I got it the brake pedal has been very soft. It has been sitting for about a year and I just started driving again after doing a long arm kit. I checked the brakes all around and had the shop do it again when I got the alignment done. Everything looks good and there aren't any leaks anywhere. I've never had to add fluid.

I've searched but haven't seen anyone with my exact problem. The pedal goes nearly to the floor even with the engine off. My only other vehicle for reference is my 87 crawler but it has rear disc brakes and the pedal is really stiff.

Truck specs are 22re(240k miles), long arm kit, Tacoma rear end with drum brakes(year unknown, but it does have the e-locker), riding on 35" tires.

It does stop and I've never lost the brakes but the pedal is just too soft to me. Problems I can think of are bad master cylinder, bad brake booster, or vacuum leak some where. I'm leaning towards the vacuum leak only because the pedal is soft with the engine off. I just want to know if my train of thought is right or if someone has experience with this.

user 82300

Before you spend almost $200 on new master cylinder or power brake booster....

There is an adjustment rod to check from brake pedal to brake booster.

Porpotioning valve

Did you and or the shop bleed the brakes on the recommended order? The manual says to do it a certain way and it works best truly.

Do you have the oem style booster and master cylinder or like a v6 upgrade?

With your truck running is there a vacuum off the vacuum line on the brake booster or: when you turn it off is there a hissing sound?

wyoming9

iTrader: (1)

you do use the Emergency Brake to keep the rear brakes adjusted ??

I bet it is not working or the rear brakes were never adjusted up correct.

Giving you the long pedal travel.

Bad Brake booster will give you a very hard pedal.

Vacuum leak will cause a increase in idle rpm

Patrick1976

@jl didn't think about the pv and didn't know about the adjustment rod.

Not sure what order the brakes were bled but the pedal is the same as before it went I to the shop.

I believe oem booster and mc. PO didn't mention changing those out.

I'll check vacuum at the booster when I get off work; no hissing when I shut the truck down and it doesn't idle high.

@wyoming honestly didn't know about the ebrake to adjust the brakes. Need to read up some more apparently.

Thanks guys

AKHeathen

start with rear brake adjustment, then bleed the rears first. it should get fairly firm off the rear brakes alone (not while running) as they need about 30 or so psi before the front brakes pressure up. you should certainly feel the difference, and it may take refilling the resivior 3-4 times at least to get an air bubble worked through. then, bleed the fronts. once done, crack the bleeders starting at the rears and then the fronts to relieve any built pressure, as it can get trapped by the pv sometimes. to give you an idea: with no rear brakes, the pedal will go nearly to the floor easily and then get hard when the fronts kick in.

Patrick1976

Thanks for all the info. I pulled the drums off and the shoes looked almost new. I adjusted the rears and then bled everything and now the brakes work. Next on my list is cooling system.

wyoming9

iTrader: (1)

Glad you got it figured out!!

Cheaper then buying a new Master Cylinder and Brake Booster as well!!!