ABS noise....among other problems

[TAvsGN]

I'm new here to the forums, but it seems like a good place to throw out my problems!! I will try and make it quick and simple. I have an 01 GP GT with 102K. Last fall, I had to have the tranny rebuilt. Right after getting it back, it had some bad road noise. Found out that Goodyear Aquatread 3's were cupped. I had a set of GY Regattas on winter tires, so I put them on early. Been nice and quiet since then with nice wear on the tires. The other set of tires had chrome GP wheels, and I was told that the chromes are heavier and might have caused the struts to wear the tires like they did. I also was unable to x-rotate the tires due to being directional. I put the chromes on the Ragattas, and so far they are wearing good. Only a couple weeks though, but the wife drives the mess out of the car. Car does not ride bad, no bouncing, struts are dry. It does appear that the upper strut plates in the engine bay are corroding. Problem #1!

Last week the wife said the brakes felt like they were grinding. I looked at them and sure enough they needed replaced. I decided to put new rotors and pads on all around. Front pads were almost gone, rears still good. Driving it afterwards, the wife and I both felt the grinding. ABS is kicking on for about a second while normal braking. It does not do it all the time, just occasionally. No traction or ABS lights show up either. Problem #2!

Can all this be related? Any suggestions? I have been looking at prices of strut packages, hubs, sensors, etc...and get scared off how much $$$ I can get into just trying this or that. A dealer repair bill scares me too. Thanks!!!

[BNaylor]

With 102K miles sounds like it is time for new struts. Unsprung weight from tires and wheels will affect strut life. The upper strut mounting plate and load bearing can be replaced when the struts are replaced.

Are you getting the noise (grinding) at all times or only when brakes are applied? You could have a wheel sensor problem causing the ABS to kick in.

BTW - What brand of pads and rotors did you install?

[TAvsGN]

ABS seems to only come on when appling normal braking.

As far as pads and rotors, Summit Racing is doing their own cross drilled rotors that have a cad plating. I figured I would try those. And the pads are VGX semi-metallic.

[BNaylor]

Originally Posted by TAvsGN

ABS seems to only come on when appling normal braking.

As far as pads and rotors, Summit Racing is doing their own cross drilled rotors that have a cad plating. I figured I would try those. And the pads are VGX semi-metallic.

The condition and quality of the rotors and pads will affect how the ABS part of the braking sysem works. I had a similar problem and new rotors and pads corrected it. I went with Raybestos Professional Grade Rotors and PG Ceramic Pads. I don't think you have an actual ABS braking system malfunction.

[TAvsGN]

The ABS chatter was going off every so often before I did the brakes.

[BNaylor]

Originally Posted by TAvsGN

The ABS chatter was going off every so often before I did the brakes.

The only thing I can recommend is to put it on a scanner capable of detecting GM Chassis/ABS codes and also monitor wheel sensor speed to see if balanced and matched. It would have to be a GM Tech II machine or Snap- On MT2500 or equivalent.

Also, if handy with a multimeter you can ohm out each wheel sensor to make sure the internal resistance is good. They will read around 1K ohms. Plus check the wiring going to each sensor on the lower control arm and to the hub.

The only time I can get my ABS to kick in is when I panic brake or when braking over a very rough road. It should not kick in arbitrarily.

[TAvsGN]

I'm going to have it checked at my mechanic. He doesn't have the ABS scanner, but he suggested other things to look at. If nothing there, I guess I will have to break down and hit a dealer. I'll post any results.