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Rusting brake parts - how do I avoid expensive replacement?

I have a 2002 Silverado 2500 HD that has had a problem with needing the disc brake components (front and rear) replaced every 20K miles with similar symptoms - rotors badly corroded, brake pads unevenly worn, and (most recently) calipers frozen in a partially engaged position. Part of the problem is me. I drive the truck only occasionallty and I have this inate tendency to avoid overuse of the brakes.

My question is, besides using it more often and trying to use the brake more aggressively, is there something hat I can do mechanically to reduce this problem?

Rust on the rotors is NOT a problem. 3 seconds after you hit the brakes from 30mph the rust will be gone.

Solution…Get better components. There should be no reason the calipers keep freezing up or uneven wear…just because the vehicle sits for a long time.

I have a similar problem with a car I drive infrequently. I drive the car more in the winter than in the summer and the problem is exacerbated by winter road salt. I made it 30K before the rear pads and rotors were shot, but it was caused by the same thing, frozen brake calipers due to rust on the slides.

The frozen calipers is what makes the pads wear unevenly.

The only solution I can think of is to take the calipers off periodically, clean the slides, and make sure they’re lubricated. I don’t think using the brakes aggressively makes any difference. The calipers slide the same distance (for all intents and purposes) no matter how hard you hit the brakes.

The other option is to drive the vehicle more frequently.

I think the concern might be rusting of the vanes between the disk surfaces rather than rust on the braking surfaces. As you say, rust on the brake surfaces is normal (at least on my cars) and is removed (on my cars) by normal braking.

  1. Drive more frequently and use the brakes to burn off rust/moisture
    B) More frequent, periodic maintenance
    III) Stainless steel calipers, ceramic pads, corrosion resistant rotors and DOT5 silicone brake fluid (assuming it’s compatible with the rest of the system)

Millions of vehicles in roadsalt country do not have problems with rusting caliper slides and rotors – even if they are driven infrequently. Maybe the engineers at GM just made some bad guesses about materials when specifying your brake parts. Next time those things fail, go to an independent mechanic and have him replace the calipers and rotors with aftermarket parts.

EXACTLY…Many times there are BETTER aftermarket parts. This should NOT be happening.

Thanks for answering my question. I tend to agree. I have other cars that sit for long periods and after a few hits on the brake, they’re good-to-go. Being an engineer heavily involved in the test and validation processes, I believe the good old GM engineers did a poor poor job of addressing this failure modes. I’m had aftermarket parts put on and we’ll see how they do. Again, thanks for the input. People wonder why I typically buy Hondas and Toyotas… I have had more reliability problems with this vehicle than all three of my higher mileage vehicles combined. It is, however, one pullin’ truck when it is not broken.
I am told that GM went back to drum brakes on the rear in 2005 because of contamination and corrosion on the rear discs - too late for me…

Honda and Toyota’s have many problems too just in different area’s and really expensive ones in differing areas. No vehicle make is devoid of problems. Buy what suits your needs, budget, and desires. If the kool-aid of Toyota/Honda appeals go for it.

I don’t think this a build quality issue at all, but more of a “who’s doing your brakes” problem.

Just offhand, it sounds like someone is overlooking caliper slide servicing.

And exactly where on the rotors is this corrosion appearing?

There exists another possible cause.

A few years back a friend asked me to help him get a car back on the road that he’d parked in his wet, dense woods behind his house. When we brought the car out we discovered that the cooling vanes had rusted so badly they had actually caused the rotor surfaces to splay out. The vanes in one approximately 90 degree sector of each rotor were caked with rust and had rusted almost through the backs of the rotors. The car had been parked there less than a year.

Yes, I’ll testify that this type of accelerated-life environment can cause this level of rotting.

So, I ask the poster, where do you park the vehicle?

The first thing I tried before the servicing was to try to loosen the pad contact area on what I think you are calling the “slide” because I suspected that the movement was of the caliper pistons was hanging up. There was actually very little corrosion in that area. I put a little anti-rusting oil to be sure. No remediation to the dragging brakes was evident. When the mechanic doing the servicing checked the piston movement when putting the calipers back on he found them to be absolutely frozen. In fact, he broke one trying to force it. Ergo, I had to have calipers installed also.
The rust build up and grooving on the pad action area was due to the pads not contacting fully because they were hung up. The pads were very unevenly worn. The cooling fins had a lot of rust, but were probably open enough to adequately cool. Especially for a Namby-Pamby brake user like me.
Thanks for responding to my question.

I live in Michigan, famous for our humidity. It was parked in the garage approximately 25% of the time and outside 75% of the time. It was never parked in standing water that I can recall.

So on which end of the truck did he break the piston from trying to force it; front or rear? There’s a reason for the question.

Needless to say, I’m a bit skeptical of someone’s mechanical abilities and diagnostic capabilities if they can actually break a caliper piston.

It was a front caliper, I believe. I did not view it, convinced that they had to replace it because I envisioned the critical components of actuation to be hung up from excessive corrosion and any rework or removal would probably not the sliding surfaces to seal adequately.
I didn’t see what he reported to be “broken”, but the manual says to use a C-clamp to check the piston movement, I agree that they probably did not use due care. Next time I will ask to view it.