'05 Chevy TB EXT
Your caliper pins are either missing the internal bushings or they are worn out. It's "torque-ing".
Can you not buy caliper rebuild kits any more? I always rebuilt them in-house to keep the cost of complete components down by buying the kits or parts needed and the labor was pure profit.The Trailblazer/Envoy series vehicles use aluminum calipers front and rear. The fronts have double pistons, the rears have single pistons--at least the ones I've looked at. Ravalli has "Cop Car" brakes which may be different.
Aluminum calipers are known for corroding behind the square-cut seal. The build-up of corrosion causes the seal to be "squished" into the piston, making the piston "sticky". The brakes still work, but the piston doesn't retract like it's supposed to. This increases brake drag. As things progress, the pistons get stiffer and stiffer until they seize in the bore, and the brakes burn the pads to nothing or the brakes quit working at all.
MOST folks would fix this by buying rebuilt calipers, which also gets you new pins 'n' bushings, fresh lube, new bleeder screws, etc.
Because I'm a cheapazz, I pull the calipers apart, clean the corrosion out of the seal grooves, polish the pistons a little, clean the scuzz out of the caliper bore and off of the square-cut seals, lube the square-cut seals and the caliper bores with brake fluid, and put 'em back together. The rears are much easier than the fronts, because dealing with two pistons is way harder than dealing with only one piston. It's not twice the work, it's like four times the work.
View attachment 58705
Wild Guess: The ABS code is not related to the rapid pad wear. I bet you find a damaged wire harness on that ABS wheel speed sensor. That, or there's rust build-up under the sensor's shim, pushing the sensor up and away from the toothed wheel in the hub.
Sounds about right --- discouraging the labor in the shop and forcing you to buy instead of the "liability" - that in reality, doesn't actually exist if you do a good job.I have had beyond excellent "luck" re-using the original rubber seals in my calipers. I've re-used the seals starting with my Honda motorcycle (aluminum calipers, pistons seized) more than once, GM iron calipers on pickups and cars, and these Trailblazer aluminum calipers.
Obviously, I inspect the rubber for cracking or any other signs of deterioration. I figure, those seals weren't giving me any problems before...it was the metal of the caliper body that was the real problem...so they're not likely to give me any problems after I fix the corrosion in the caliper, and clean out the crusty deposits and muck in the caliper bore, piston, and rubber seals.
That said...I've never done this on a "customer" car. Only my own vehicles.
I haven't even tried to buy caliper rebuild kits, or wheel cylinder rebuild kits in decades. The kits cost as much as "rebuilt" or sometimes even "new" parts; and you don't get a warranty with the rebuild kits.