Hi, There is a great DIY article on this site showing replacing the front brake pads, and it recommends replacing the caliper bolts when the calipers are removed to replace the pads. I did that job, and the bolts are about $10 each. I am preparing to do the rears and I cannot find any DIY, and I am wondering about the bolt replacement. I guess 'yes', and it turns out the rear bolts are about $40 each. Wondered if anyone knows if these bolts need to be replaced?
Thanks

 

Given how thick those bolts are, one would be tempted to reuse them, but I wouldn't. Risks are too high. If any one of those bolts fail, you will loose braking to that wheel at the very least, possibly loose control.

 

www.suncoastparts.com/mm5/merchant.mvc?Screen=PROD&Store_Code=P&Product_Code =991CBO

 

Don't have the factory manual for the 991.1 cars but in my 996 Turbo factory repair manual there's this:

Note

Replace the brake caliper fastening screws after each removal.

I seem to recall this same note was in my Boxster's factory repair manual.

When I did the brakes on my Boxster I replaced the pad and rotors, the wear sensors, and ordered a brake hardware kit from the parts department that contained new retaining clip, clip pin and spring clip, new rotor/hub retaining screws for each wheel. IIRC caliper bolts were ordered separately as were the wear sensors. While I no longer have the factory repair manual the above was I'm pretty sure by the factory manual.

The bolts are not stretch bolts. At least for the Porsche vehicles I owned.

I believe the reason they are not to be reused is I noticed the new bolts had a special metal surface treatment sort of like a coating or plating but it was not shiny, slick, cosmetic in nature but instead had a powdery appearance but was not flaky or loose. It was on the whole length of the bolt, including the threads. The powdery appearance of the caliper bolt threads reminded me very much of the appearance of the threads of factory replacement spark plugs.

Believe the coating/metal surface treatment was a substitute for thread lube and acted in some way as protect the threads mainly those in the caliper. The bolts are much less costly to discard and replace than the calipers. In spite of their exposure to the elements -- when I drove my Boxster in the snow and parked it the slush under under the wheel wells would melt and rain salty water down on the brake hardware -- and of course heat -- the bolts came out of the caliper with no trouble at all.

Like spark plugs I treat caliper bolts as a use once item. Install them and torque properly and then when it comes time to remove bolts (or plugs) -- for any reason but in experience with my cars the plugs and the caliper bolts only needed to be removed at the next plug change interval or the next time the brakes needed attention -- replace the caliper bolts (or plugs) with a new ones.