Excessive Brake Pedal Travel

mkory · September 7, 2009

After a close call having my brake pedal go to the floor a few weeks ago when one of the metal lines burst, I had all of the brake lines and hoses replaced, as well as the two rear calipers. All pads and rotors are new as well. Since I've gotten the truck back from the shop, it seems like there is significantly more brake pedal travel than before. The pedal travels what feels like a few inches before there is any resistance/stopping power at all. Once past that dead band, the brakes feel like they used to. The only "old" parts on the truck now are the front calipers, abs module, and master cylinder. Any ideas why this has happened?

brims · September 7, 2009

Possible air in the system?

mkory · September 7, 2009

Possible air in the system?

I doubt it. I watched them bleed it. The shop is very reputable, and they used a machine that pressurized the master cylinder, as well as one that cycled the ABS pump.

rogerf · September 7, 2009

Possible air in the system?

I doubt it. I watched them bleed it. The shop is very reputable, and they used a machine that pressurized the master cylinder, as well as one that cycled the ABS pump.

Probably yes...bleed the system again. The next possibility is the master cylinder is beginning to fail.

ironhead3fan · September 7, 2009

That very same thing happened on my 1990 Silverado. Never was able to get the entire pedal back, even after replacing the master cylinder, and power bleeding the brakes.

Spurshot · September 7, 2009

It's simple enough to check for air in the lines: Pump the pedal (with the engine running for the power assist) and see if the pedal comes up. If it does, it's air. If not, I'd a rear drum equipped (you have rear disks... right?) for adjustment, then I'd suspect the master cylinder.

mkory · September 8, 2009

Hmm... the pedal does not come up when I pump it. So next look into the master?

Wouldn't I be losing fluid if it were the master?

Spurshot · September 8, 2009

Hmm... the pedal does not come up when I pump it. So next look into the master?

Wouldn't I be losing fluid if it were the master?

Not necessarily.

mkory · September 15, 2009

The problem was actually in the front bearings. A few days later I noticed noise from the front bearings. The left front wheel had so much play that it must have been pushing the pads far enough from the rotor to increase the pedal travel. How about that.