Pulsing brake pedal

[kpc01]

I have a brake pedal thats pulsing pretty good when you hit the brakes. the steering wheel has a slight shake but NOTHING compared to the pulse. I was told this means it is the rear rotors but I wanted to get some more input. Its obvious I have some warping somewhere just trying to pinpoint it before I tear it all apart. Plus I have to order the rotors so I'd like to get some on order first.

[JimD]

Think i'd be checking the front rotors first(warped).

[openroadracer]

another vote for warped front rotors.

[94mstng94]

Sounds like you have both... a slow speed pedal pulsation usually leads to rear rotor warpage. High speed steering wheel shudder is obviously the fronts.

[Rustang]

First, what's it on? Depending, you can use the park brake to diag it. Some rear disc use small shoes inside the rotor for a park brake, so it won't work in those cases. But, like already stated, probably fronts... Dial indicator is the best way to check them, but you can hold a small screw driver next to the rotor surface and see any run-out while you spin it.

[LS1Goat]

rotors are warped.

[kpc01]

First, what's it on? Depending, you can use the park brake to diag it. Some rear disc use small shoes inside the rotor for a park brake, so it won't work in those cases. But, like already stated, probably fronts... Dial indicator is the best way to check them, but you can hold a small screw driver next to the rotor surface and see any run-out while you spin it.

thanks for all the input, its on an 08 Armada. I will pull the fronts off this weekend hopefully. I thought it would be the fronts but just wanted some other opinions on it. I will probably look into getting them both turned (if possible) and going from there.

[SC457A]

A pulsation in the brake pedal is generally the rotors surface is out of parrallelism. (warped rotors).


The rotors push the brake pads back into the calipers (push the brake fluid back into the applying master cylinder) unevenly as you brake. Can also be felt as uneven braking.

Hardest part is finding out which rotors to cut. ( I look at it a little different, stupid warranty claims)