2001 Silverado - ABS kicking in just before completely stopped

chevrolet
1500

#1

2001 Chevy Silverado, 2wd, 5.3 engine, 232,000 miles, front hubs with integral sensors replaced about 20,000 miles ago. Now when I brake, and just before coming to a complete stop, the ABS kicks in. Doesn’t happen if I brake hard. If I let up on the brake momentarily, it stops and the rest of the stop is smooth. Sometimes the brake and ABS lights come on, but when I had the OBD hooked up, there were no stored codes, and the brake and ABS lights go off once you turn the ignition off and then restart the engine. I suspect the problem is with the sensors for the rear wheels, but don’t know where they are located. There are no wires going to the rear wheels or the axle.

Tried pulling the fuse for the ABS system, but that makes the brake and ABS lights stay on constantly.

Any insight would be greatly appreciated. I try and fix things myself first, but this on has me stumped so far.


#2

Since I posted this, and didn’t hear from anyone, I looked elsewhere and found that this is a problem with t TSB - TSB 03-05-25-007D. The problem is caused by corrosion at the sensor which increased the gap between the sensor and the hub reluctor ring due to a build up of rust or gunk. The fix is to remove the sensor and clean it up (if you don’t break it getting it out). The TSB is available on-line and details the repair.

Thought I would pass this on.


#3

@sanzone, this is gonna sound a little strange but… I had the same problem with my '04 Avalanche. I found the TSB and was ready to pull the sensors. I noticed the truck was lower on one front corner than the other. It had sagged a bit over the years. Since it was a 4WD model, it had torsion bars with a bolt to adjust ride height. I cranked up the low driver’s side and darned if the ABS problem didn’t go away completely, never to return. That isn’t as easy a fix on your 2WD truck, but put it on flat ground and measure the fender lip to wheel rim on each side to see if it is level. You can buy spacers to boost the height at the front for a few bucks just to try it rather than risk breaking a speed sensor at a cost of $90.


#4

Hey Mustangman, I appreciate the input. I will check what you said before doing anything further.

In the meanwhile, if I do break the sensor in trying to get it out, and while the sensor does cost what you said, I can get a whole new bearing and hub including the sensor for $115 plus shipping off the web. That is my plan right now - try and fix it by cleaning the corrosion, and if it breaks, just go for a new bearing, BUT I will try and prevent future corrosion by putting some anti-seize stuff on it before installation.

Come to think of it, everyone with this vehicle should do this before installing a new wheel bearing and hub the next time they have to replace the bearing.


#5

I agree with you on the wheel bearing, that’s what I did. Your 2WD should be easier. I pulled the knuckle OFF my 4WD. 3 tapers and out it comes. It was easier to get an impact wrench on the bolts AND I needed my hydraulic press to get it out of the knuckle. With a 2WD, bolts should be better and you can whack it with a BFH to get it out of the knuckle.