Brake Caliper Fasteners

[hobrien]

I was checking Alldata for the procedures for changing the front brake pads on my 99 FRC. I may have misinterpreted something, but it appears to me that they suggest replacing the caliper bolts whenever the caliper is removed from the rotor.

I don't mind replacing them, but I have not done that on other cars and I am curious about why. I am planning on changing the pads soon, and I am just trying to figure out exactly what parts I need to gather. Any help or advice will be appreciated.

[vettex2]

it's a liability thing mainly
I've reused them w/o issues.

[LLC5]

I have reused the bolts also.

I would imagine that as a high performance sports car that can be used on a race track, it is prudent to advise replacing any bolt that is removed. Any time you tighten/torque a bolt it stretches, and re-torquing a stretched bolt is technically never as accurate as a new bolt. Add that on to the fact that the used bolt could be fatigued, you can see why G.M. recommends replacing instead of re-using.

[aquaholic]

maybe those particular bolts are torque to yield bolts. which essentially means that they will not spring back to their original size when torqued to a predetermined rating. the yield point of a bolt is beyond the elastic range so the metal comprising the bolt will never have the same molecular structure once the yeild point has been reached.

[vettex2]

Originally Posted by aquaholic

maybe those particular bolts are torque to yield bolts. which essentially means that they will not spring back to their original size when torqued to a predetermined rating. the yield point of a bolt is beyond the elastic range so the metal comprising the bolt will never have the same molecular structure once the yeild point has been reached.

could be, but i reused them on every car I've owned and also reused them on every brake job I did when I worked as a mech. in a shop.
I also reuse them on our race cars.
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[aquaholic]

i am not sure those bolts are torque to yield. however, that may explain why the manufacturer requires replacement. you can absolutely reuse a torque to yield bolt but the bolt will not be of the same strength as it was before it reached it's yield point.

Aren't those bolts under shear loads?

[flir_man]

Yes, they are in shear. My 2000 Helms manual only states to replace if they show wear or are damaged. How they would wear if torqued is beyond me.

My point exactly. It sounds like a lawyer wants new bolts. I can see if the bolts have been torqued so much you have approached their tensile strength and they are ready to pull apart, but beyond that it seems to me re-using them should be fine.