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View Full Version : No brakes on 2003 Chevy Silverado


RELIABLELAWNMAN
04-23-2008, 09:14 PM
First I would like to say that I received good info. on changing the fuel pump on my sister-in-law's 2001 Chevy. Lifted the bed and changed the pump w/o
dropping the tank.
Now my brother-in-law who has a 2003 Chevy Silverado, 4.3 liter engine and 4
wheel disc brakes. There is no brake pedal at all. I moved the master cylinder forward from the brake booster and saw no brake fluid. No fluid is visible at all possible locations. I opened the right rear caliper and only got a trickle of brake fluid. There is no pedal even with the engine off. Should I take the M/C
off and try to bleed it to see if fluid is pushed from the reservoir? I thought about removing the bottom lines from the combination and see if fluid can be pushed thru this valve. Any ideas are greatly appreciated.

PTP
04-23-2008, 10:01 PM
There are a couple of good possibilities.

1. There is air in the brake system. This is likely if there has recently been some work done. If there is air in the system, it is a secondary problem that is caused by some other problem - like a leaking caliper, line, etc.

2. There is a leak somewhere. A line could be cut, a caliper could be leaking, a hose could be split, or the master cylinder could be leaking.

3. The master cylinder could be leaking internally. If the fluid level has never run down and there is no evidence of leaking anywhere, then it is possible that the internal seals on the master cylinder are bad.

Did anyone put anything other than brake fluid in the master cylinder? Anything else will completely ruin the internal rubber parts and will cause major problems - like the one you described.

There is your checklist. It is almost certainly one of those problems. Hope that helps.

rjxj
04-24-2008, 04:50 AM
Like PTP said, if it hasnt been worked on and the pedal goes to the floor with no leaks it would be possible that the master is leaking internally. When you work on this system it can be hell to get the air out. In fact it may need the tech 2 tool to cycle it while bleeding to get the air out. You may need to research that issue.

RELIABLELAWNMAN
04-24-2008, 09:48 AM
Thanks for the replies.
Last Aug. he had a rotor and pads put on. The system seemed to work OK one day and then the next morning the trouble started. Would the M/C leak inside and not be visible from the outside?
Thanks again.

TOOMUCHWALKING
04-24-2008, 11:43 PM
I've had several vehicles let the pedal hit the floor a couple of thimes after collapsing the pistons back into the calipers to fit new pads. Yours sounds like the fluid went somewhere...

PTP
04-25-2008, 12:04 AM
Thanks for the replies.
Last Aug. he had a rotor and pads put on. The system seemed to work OK one day and then the next morning the trouble started. Would the M/C leak inside and not be visible from the outside?
Thanks again.

Yes, if the internal seals are leaking, the fluid level will stay the same but the pedal will go to the floor.

Normally, there will not be no pedal, there will only be a fading pedal (it slowly goes to the floor). However, if someone put something other than brake fluid in the master cylinder, you will have no pedal at all.

If you take the cap of the master cylinder off and the rubber in the cap looks deformed, then you have bad fluid. If the rubber looks normal, then you have some other problem.