06 Silverado Brake Issues

[Fishinguy40]

2006, Chev Silverado, 5.3L-V8 with 56,ooo miles.

Occasionally, when I am creeping to a stop at a red light or stop sign, the brake pedal almost feels like the anti-lock brakes are kicking in. There is a pulsing feeling in the brake pedal but instead of a firm "bouncing feeling" in the pedal, the pedal travels all the way to the floor. The brake pedal is firm but then suddenly it gives a little, stops, then gives a little bit more, stops and then gives a little bit more and stops.

It doesn't do this often. It only does it a very slow speeds, such as coasting to a stop. Doesn't matter if the weather is wet or dry. I am confident that none of the wheels are locked so the anti-lock brakes shouldn't be kicking in.

Two months ago I replaced the front pads and rear shoes. I added brake fluid to the resevoir as the level was low, even after retracting the calipers. I have not been able to find a leak any place and the level seems to be holding.

Is it possible that one of the brakes are hanging up and that is why I get the travel, stop, travel, stop? I wonder if one of the rear pistons is "walking" in the cylinder. Thoughts or ideas?

[Macgyver55]

Nothing you did would affect this. It sounds like the front wheel speed sensors need to be serviced.

Previous thread on this problem

[Fishinguy40]

I thought about the wheel sensors but I don't think the ABS is actually kicking in. I could be wrong.

When the ABS does kick in on ice or snow you can feel the pulsing and the brake pedal jump. With this issue, the brake pedal is firm but then goes to the floor in 3 or 4 short and quick "surges" (maybe not the right term to use). The brake pedal never jumps back until you take your foot off the pedal. Then it doesn't do it again for several days or weeks.

[Macgyver55]

I thought about the wheel sensors but I don't think the ABS is actually kicking in. I could be wrong.

At slow speeds less anti-lock assist is needed because you are stepping on the pedal lighter so the "sensation" of the pulsing is lessened.

I'm fairly confident (without driving it) that corrosion under the sensor is your problem, this is text book symptom of the service bulletins concerning this on earlier models. In fact, I just did a set yesterday with the identical symptom, and have done many others in the past.

[Fishinguy40]

I will take a look this weekend. Thanks!