dparm

After ~20 hours of track use, the dust boots on my OEM Brembo calipers have fallen apart. My dealer, my shop, and my brake supplier have said this could also indicate hardened pressure seals -- and that I should consider a caliper rebuild (the dealer said to just replace). My shop said it's "several hours" at their normal rate of $150/hr, plus the cost to remove and reinstall the calipers, plus the cost of parts from Brembo. That sounds like a grand.

How often are people rebuilding calipers? Are there any warning signs? Is there a company you recommend for this, or is a competent race shop able to handle this?

I see that brand new OEM calipers can be had for $450ish...so it's tempting to just replace the caliper outright and then rebuild it myself and sell it as used. Am I crazy for thinking this?

BT Racing

Dust boots? I can burn them off in 5 minutes. Throw them away and forget about them for the track. They don't do anything.

dparm

No argument there, I agree it's only a matter of time.

Do you agree with the sentiment that the pressure seals inside the caliper are going to wear down over time too, and at an accelerated rate if there was sufficient heat to burn up the dust seals? Even if you don't agree with that, what's the lifespan of a caliper that's on the track? 20 hours? 40 hours?

Gary2KC5

yes the pressure seals need to be replaced. I'm getting ready to do mine...$35 for seals and my time. it's not hard to do just time I could be doing other things. I tend to spend money on things I can't do myself like make tires. Some things I will pay to have done, but rebuilding calipers is within my skill level. if you can change brake pads, it's not much more difficult. Granted, a lot more work and you need a good bleed when your done...maybe a couple times. this is the other thing; the dealer is only going to bleed them once.

Bill Dearborn

Rebuilding calipers is fairly easy and GM has a kit that contains everything required including small packets of brake lube. Just don't reinstall the dust boots. On my track calipers I wait until I see some dampness and then change the seals. You can get quite a few track days between changes. The biggest thing is to keep dirt from getting into the seals so I spray the pistons with brake clean to get any dirt off them before depressing them into the caliper.

One thing that is required is brake caliper assembly lubrication (included in GM kits) which is hard to find at auto parts stores nowadays. Nobody rebuilds calipers now so the only brake lube they stock is the stuff that lubes the slides on slider calipers. The only counter workers who know what you want are the old guys the new guys will look like deer caught in a headlight. I found my caliper lube at Zeckhausen racing https://www.zeckhausen.com/catalog/p...ducts_id=26612 . It really makes pushing the pistons back into the calipers easy. Brake fluid won't cut it. They also have caliper rebuild kits for the C7 Brembo calipers https://www.zeckhausen.com/catalog/i..._103_5722_6495.

Bill

dparm

My dealer Corvette tech said that GM does not rebuild calipers. They would need to be replaced.

And yeah, I know Zeckhausen -- I have been ordering from Dave for years. He knows his stuff! My shop has advised against using the Centric parts. They said it's best to go straight to Brembo.

tw78911sc

If the pistons are aluminum upgrade the pistons to SS or Titanium to reduce heat transfer to fluid.

dparm

Getting off-topic here. Pistons need to be made of the same material as the caliper. Several big brake manufacturers have said this repeatedly.

anth115

Hey, I just rebuilt mine so I wanted to share my experience:

Note - this is for the C6Z oem PBR calipers. Your post mentioned Brembo's, but the general process should be identical.
- Rebuilding the calipers is very doable if you can scrounge up ~2 hours a night, you'll have it done before the weekend for sure. My first one took me ~3 hours and my second one took me 1-1.5. I had no prior experience in this area.
- My rebuild was also necessitated by melted dust boots. Figured this was a skill worth learning if I was going to continue with HPDE. My internal pressure seals were fine, but obviously changed them while I was in there.
- Centric makes the rebuild kits for the C6Z calipers as does AC Delco. The Centric kits are ~$15/ea on rockauto and include the pressure seals and dust boots. The more costly Delco kit includes more, but I didn't need any of that.
- There are a few tricks that helped immensely during the process. I will post a separate thread as a DIY guide for this topic, so if you go ahead with the rebuild, just PM me and I'll link you to it. Wanted to keep it in a new thread for better visibility for other members; just need to find a few minutes to put it together.
- As for warning signs, there aren't many that come to mind except to remember that when your pads are nearly gone, a lot more heat gets sent to the caliper. That's what melted my dust boots. So when you head to the track, bring an extra set of front pads so you don't ruin your day, and I imagine better cooling via spindle ducts would also be a big help.
- For the stainless pistons, I don't know if your caliper already has them or if they're even available, but DRM has offered them for C5-C6 cars for years and I haven't heard any complaints. I understand your point re: metal expansion rates, but perhaps the amount is minimal or the seals compensate for the difference. I did these while I was in there.
Good luck & hope this helps.