2001 chevy pick up 1500 4x4

2001 chevy 1500, Z71 4x4 shortbox, 4.8L 71000 miles.

I wonder if anybody else has ever had this problem. My anti lock brakes will kick in during braking. It only does it once and a while, 1 out of 10 times braking. It seams to do it when I’m pulling into a parking stall and 5’-6’ from being stopped it will start to activate. It has done it in reverse backing down my drive way also. I have checked my brake pads and rotors, they are very good. This truck has four wheel disc brakes. I thinking it might be a sensor. Is there any way to check those?

Thanks for your help:)

I have never been impressed with the ABS implementations on their pickups. Here’s what I would check initially; Tire pressures- make sure they are in spec and equal side to side on an axle. Hall effect sensor- check for wheel sensor position/alignment and dirt buildup. Tone ring- check for cracking in the ring that expands and contracts with temperature.

I have checked tire psi. They are all equal and good. I was thinking of pulling the wheel sensors and checking for rust or dirt build up. I’ll let you know what I find. Thanks for your advise.

There’s a GM TSB#03-05-25-007D dated 5/1/09. This addresses the problem of low speed ABS activation.

The problem occurs when rust accumulates under the wheel speed sensors. This causes the wheel speed sensors air gap to hub tone rings to increase. The fix is to remove the wheel speed sensors and remove any rust from the sensor mounting surfaces, and apply grease to the sensor mounting surfaces to prevent further rusting. Also inspect the wheel speed sensors for distortion of the sensor mounting ears. If any sensors are distorted they are replaced. Also, while the wheel speed sensors are removed, clean the sensor tone rings with a sensor safe brake cleaner.


Thanks a bunch. That sounds just like my problem. My plan is this weekend to get it up on the hoist. Then I can pull the sensors and check them out. Thanks for your help. I’ll let you know how it goes.

That was the problem. I checked my voltage and it was very low. I pulled the speed sensors cleaned up the mounting surfice and reinstalled and checked the voltage and it was right up where it should be. Amazing such a little problem of rust created such a problem. Thanks for all your help guy’s.