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steelforrest
09-24-2000, 04:24 AM
I have a 1987 Suburban(3/4 ton, 2wd, 454/th-400, 14-bolt full floater axel, 13in. drum). I just replaced the rear shoes and wheel cylinders, I am having trouble bleeding the brakes. I have already put half a gallon of fluid(literally) through the system, and the brakes still go to the floor. All of the lines bleed clean(no air), and the lines are all secure and dry. I did the front calipers and master cylinder a few months ago and the brakes were ok. The brakes have never been good so to speak, but they have always stopped the truck in a reasonable distance. Can anyone help me? What could be causing this problem? Any help would be appriciated -Steelforrest

John DiMartino
09-24-2000, 08:11 AM
Did you rebleed the front system?If the proportioning valve let a little air thru or went to the front side (normal when you open the system),it might be stuck there,if you pump the pedal as fast as you can to get some kinda pressure,as soon as you have pressure,have a friend open either of the front bleeders,this will pop the valve back to center,finish bleeding front,then try the back again.If thats not the problem,make sure that the brakes are adjusted properly,the E-brake cables are fully retracted,and not sticking on a little.Sometimes they get rusted and stick a little,then you cant get a good adjustment on the rear shoes,this will give a slightly spongy feel,but not a total loss of pedal.You are sure that there aren't any leaks at the fittings on the new wheel cylinders,right.Any leak,even tiny will prevent removal of air from system.If this fails try a powerbleeder,front and rear.Good luck

OBRYANMAINT
09-24-2000, 03:07 PM
i second that problem may be at proportioning valve

cat320
09-24-2000, 09:03 PM
I think he might be right with the propotioning valve i had a truck and the same thing would happen to it.