Brakes

[SunlitComet]

the sound you seem to hear is just the airflow within the booster and should be normal. the binding could be a pison in the caliper or mc or the caliper body itself machined surface binding on the caliper adapter machined surfaces. not talking lines at all, the other related parts, sorry.

 

[Mike McCloskey]

the sound you seem to hear is just the airflow within the booster and should be normal. the binding could be a pison in the caliper or mc or the caliper body itself machined surface binding on the caliper adapter machined surfaces. not talking lines at all, the other related parts, sorry.

Thanks, I think I will check out the calipers and possibly replace the master cylinder. Sound reasonable?

 

[Mike McCloskey]

Thanks, I think I will check out the calipers and possibly replace the master cylinder. Sound reasonable?[/QU

the sound you seem to hear is just the airflow within the booster and should be normal. the binding could be a pison in the caliper or mc or the caliper body itself machined surface binding on the caliper adapter machined surfaces. not talking lines at all, the other related parts, sorry.

Just noticed when driving home that the brake pedal was very hard to push and had a hard time stopping the vehicle. Also, when I press the brake the engine rpm does vary a bit and when releasing brake from a stop and accelerating, the engine faltered a bit (inconsistently).

 

[69fury]

What was the cure? my 95 Yukon SLT has what I would say normal pedal unless I jump on it quick- then it's rock hard and slowly goes down. Brakes work fine when used normally, but I just bought it last fall and maybe I don't know what they're "supposed" to feel like. Pulled the ABS fuse-no change- tried it with left foot while on the throttle with right foot and then without being on the throttle-no change. Tried at speed and at idle. It all seems to be tied to how hard/quick I hit the brake pedal. haven't tried it with the engine off yet. Thanks in advance-Rick.

 

[Mike McCloskey]

What was the cure? my 95 Yukon SLT has what I would say normal pedal unless I jump on it quick- then it's rock hard and slowly goes down. Brakes work fine when used normally, but I just bought it last fall and maybe I don't know what they're "supposed" to feel like. Pulled the ABS fuse-no change- tried it with left foot while on the throttle with right foot and then without being on the throttle-no change. Tried at speed and at idle. It all seems to be tied to how hard/quick I hit the brake pedal. haven't tried it with the engine off yet. Thanks in advance-Rick.

Replaced the master cylinder (may not have been the problem) and the brake booster. They are great now. I have have had this issue with Chevys before. I think it was the bad booster.

 

[Mike McCloskey]

Replaced the master cylinder (may not have been the problem) and the brake booster. They are great now. I have have had this issue with Chevys before. I think it was the bad booster.

BTW, when I removed the master cylinder, I took a pipe cleaner and stuck it in the hole in the brake booster where the master cylinder attaches to see if there was any oil at the bottom. There was, indicating that it was leaking oil and needed to be replaced.

 

[69fury]

Thanks for the heads up- hate to do both, but I might just have to bite the bullet.- Rick.

 

[69fury]

Update- the booster still holds vacuum after 2 1/2 hours of sitting- no issue there- but the master will slowly go to the floor with engine running. Since the code tag on the glovebox door shows I should have the smaller piston master cylinder, I'm thinking this is what the situation is: larger piston MC installed, which works fine when it's bypassing a bit, but if you stomp on the pedal the seals work a bit better-at this time the too-large piston rears it's head and gives a really hard pedal. Sounds good in theory, right? i'll change the master out and try to measure the old one's bore.-rick