Brake question..need help fast!!!!

[bckinblk]

I just replaced one of the front calipers on my 97 tahoe and I bled all the brakes but now the truck seems to have trouble stopping and the brake pedal is very spongy and close to the floor ..I checked all fittings for leaks and all is good and I also refilled the resevoir with new fluid and it still is'nt right .what could it be ?? thanks in advanvce for any info..........

 

[HarryH3]

Did the resevoir run dry while you were bleeding the brakes? That will let a lot of air into the lines. /forums/images/icons/frown.gif

Another possibility is that the master cylinder went bad. Sometimes some dirt/rust/etc. will build up a ridge at the end of the "normal" stroke of the master cylinder. When bleeding, the brake pedal goes down further, and pushes the seals on the piston in the master cylinder past the "ridge". The seals get cut/torn and then they don't work properly any longer. /forums/images/icons/mad.gif

 

[Twiz]

Double up on what Harry said.

Also,
Will the pedal "catch" if it's pushed on hard and fast?
If it does, does it fade away with constant pressure applied?
If that fitts your problem, there is a pretty good chance the master-cyl went belly-up.
(could also be the prop-valve, I've seen those do the exact same thing)


If the pedal is allways soft, and never comes around, (unless pumped-up) then it's probably just air in the lines.

 

[BlazerGuy]

You could also take it to shop and have them 'power-bleed' it.