Front brakes / Top caliper stud

[rwandrew5270]

All was going well on a front brake job on my 99 /996 911 Cab until the last stud on the driver side caliper. Not sure the cause but several threads galled making it very difficult to remove but I did get it out. I took the other stud and chased the threads and luckily it worked. I ordered another stud, but is it ok now that I'm down 3 threads out of 6 threads that engage (1/2 strength)? Not sure what the stress load on a caliper is under normal driving conditions (I don't track the car at all), will 1-1/2 studs do the job? Looked at a used lower suspension spindle hub knuckle (996.341.657.11) should I replace? What do you think, Bob?

[tonythetarga]

You might want to look at a helicoil installation. You could also use an anti-sieze compound for threads to prevent future damage. Over tightening is also a problem that can cause threads to pull out.

[rwandrew5270]

I spoke with the local Porsche dealer (Wilmington) and he said 1) that the hold down bolts should be replaced every time you remove the caliper, so I purchase a set of (4) for the front. And 2) they should be torqued to 63 ft.lbs.. So I have replaced all (4) and they are all properly torqued. The one stud in question has more thread engagement than previously noted and I plan on replacing the steering knuckle when I change out the shocks in the future. Also pull the wheel in a month to check the torque. Hats off to Wilmington Porsche for the great information to a do it yourselfer like me!!