Caleb's Brake Issues
From Fusselman.org
Caleb has been having some issues with his ABS system on the (2002 full-size Chevy) truck he's been driving recently. Not the least of its problems is that, at 19' long, it's too big for my garage. Anyhow, it's been engaging the ABS at low speed, even when the surface is totally dry. Back in '06, there was a warranty/recall for such a problem, where the dealer supposedly checked, cleaned and sealed the sensors on both front wheels. (Said Truck has no rear ABS sensors, even though it is 4-wheel disc brakes).
Anyhow, the word on Google is that the issue can be resolved by performing similar maintenance again. So we got started by tearing down both front spindle assemblies to get to the sensor, which is strategically located underneath the disc, behind the heat shield.
To get to the sensor, you have to remove the wheel, brake caliper (and its associated carrier) and the disc itself. We laid the caliper up on top of the arm assembly (Which I've never done before, since cars don't really have space there) so we could leave the hydraulic lines connected. This turned out to be the hard part. Of the 2.5 hours we spent at Blakes, almost 90 minutes was spent taking the discs off, as they were rusted solid. Lots of WD40 (in the absence of real penetrating lube) and banging with a deadblow hammer (on the hub, not the friction face) eventually freed both rotors.
From there, it was pretty straight forward: 1 cap-head screw holding down the sensor, which was pressed into a hole. A good cleaning was given with electrical contact cleaner and compressed air and we put it all back together. The sensor wires are pretty heavy duty, presumably to protect them from road grime; This, however, presents a problem when trying to maneuver the sensor through the hole in the dust shield and into their sockets, as the wire doesn't want to bend very well, making it tough going.
Now for the sad part... After we got it all back together and were backing out of the driveway, it did it again! Basically, an entire evening wasted discovering that I have a small garage and disassembling and reassembling Caleb's brakes "just for fun"... Not really sure where to go next, but I suppose that the answer is back to Google... I'm still suspect of a sensing issue of some kind, but I'm not seeing any physical problem with the sensor. I'm also unclear if it could be a modulator issue, and if the left and right wheel modulate separately. Time will tell.
Seth: I know you had links for all this stuff, can you email them to me?
