99 sierra abs

When pressing the brake pedal on my 99 sierra 4x4, my anti-lock wants to kick in at 5mph. Dosn't matter what speed I'm traveling, when I decelerate
to 5mph, the anti-lock kicks in. Even worse, if I happen to hit the brake at exactly 5mph the brake pedal really 'locks' up and I have to pump the brakes like a mad fool to stop. This is a real problem when turning into a parking spot at the mall!!! Any ideas would be greatly appreciated,
Thanx, Mhud
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Bill wrote:

It would be quick to check the brake fluid level in the reservoir. After that, the wheel sensors, connectors, and wiring.
---Bob Gross---
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May not apply to your truck, but my 94' Z34 did the same thing. It was the right rear wheel bearing going bad allowing the wheel oscillation to fool the sensor. I realize that you have rear drums but possibly the fronts could do the same.
Brian
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If you have this scanned with an abs capable scanner you will see one wheel sensor drop out before the others, usualy one of the fronts on this truck, sometimes the problem can be corrected by removing the wheel sensor and cleaning the mounting area on the hub and sensor flange and reinstalling with anti corrosive lube on the area on the hub, or the wheel bearing assy will have to be repalced.

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Bill Silcox wrote:

What Shep says. I just saw a notice come across the shop foremans desk this morning that says GM is planning a safety recall for this very issue. This notice I saw says that only the provinces of Ontario and east from there will be covered (probably because of the high amount of rust related problems down there).
Ian
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Thanx for all the great advice guys. I think I'll call the dealer and ask if a recall is in the works for my local area (MI). No use me gettin dirty for nothing.
Thanx again,
Mhud
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Bill Silcox wrote:

Don't be surprised if they know nothing about it, or claim to know nothing about it. I'm also not sure if it extends back to your year of vehicle. Sorry, just the standard disclaimers. When the recall is offcially released, I'll have more info.
Ian
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