Can anyone explain the real reason why the GM service manual has a warning about replacing the caliper bracket bolts with new ones... (and why it doesn't simply tell you to use thread locker)...?

 

dont forget to check the slides and make sure there lubed up. and USE threadlocker on the bolts.

 

I started researching this a while back and never finished. I have a '99 and believe that earlier years had tighter torque specifications that actually yielded the bolt. (If someone has a '98 or earlier, please chime in.) In that case, you'd definitely need new ones each time. I started doing the stress calculations for our bolts and found that the updated torque specifications don't yield the bolt.

The only other thing I read was that re-torquing these bolts can wear away the black oxide finish and reduce the friction of the threads. This would, in turn, make the bolts more prone to vibrating out. At the torques we are talking about, threadlocker really isn't that effective.

 

What are the part numbers and bolt dimensions for the caliper bracket bolts (front & rear)...?

(are the front and rear bolts the same or different...?)

Can these be replaced with equivalent grade 8 bolts from elsewhere...?

 

Front and back are identical 12mm bolts. I just bought them from the dealer; $5, 1 in a bag and they came with red locktite on them.

Sorry Joe I don't have the length. The GM part # is 14067559

 

I feel stoopid; you said caliper bracket, not the caliper bolt itself. Sorry, the bolt is 18mm for the bracket, front and back. I don't have the GM part number or length.

 

No worries...

I have been to several places and they all promptly produced the caliper slide pin bolt...

 

I was cussing for about 10 minutes minutes when the caliper mounting bolt was spinning unti I figured out a 16mm wrench was need to keep that sleeve from spinning. LOL Check out figure 4.

 

+1 for lubing the slider pins. I had a couple freeze up on me. Not fun.

 

The front/rear bolts are different. You must use high strength bolts. Grade 8 are too weak.

The following threads have information about the bolt grades and GM part numbers. I haven't come across any aftermarket place that has a comparable washer head high strength metric bolt. Even if you could find one, I doubt you could get it for much less than you can from an online dealer like gmpartsdirect.

https://ls1tech.com/forums/suspensio...f-freeway.html
https://ls1tech.com/forums/suspensio...ur-brakes.html

 

Ok, thanks, these are the part numbers I got from those links:

18023646 = front caliper bracket bolt
10229606 = rear caliper bracket bolt

 

I would recommend flushing the fluid at every brake job. It's about $4 a quart and will prevent bigger issues down the road. Anything worth doing is worth doing right. Get the fluid, flush it, bleed it, sleep easy.

Also, try to use only ceramic or silicone based lube on the pad abutment clips. The autozone anti-seize silver stuff will run under high temps and not provide any real lubrication at those points!

 

Yes, I do both (flush fluid every brake job, and use Permatex silicone brake lube on the clips and slide pins).