[BobSaabit]

I need to drill one out on a car... do I need cobalt drills or is it soft steel?

 

[jvanabra]

I strongly doubt it. It's just there to ease assembly, it's not doing any work. Usually all you need is a torx driver to totally mangle it. womp womp

 

[BobSaabit]

Yeah, already peened it in and got a great grip with the 3/8" drive allen wrench, still won't budge. I was actually twisting the allen wrench and it wasn't moving. Hammered on it a lot to break it free. No luck. No torch allowed... down to the drill it off option (or maybe freeze spray, might be able to shrink it). But I'd like to go back prepared.

 

[jvanabra]

A big easy out could work, but you could probably just as easily drill off the head.

 

[jmkcc]

Definitely not hardened, I've had to drill out several. Friggen insane choice of fastener in that environment.

 

[BobSaabit]

Definitely not hardened, I've had to drill out several. Friggen insane choice of fastener in that environment.

Thanks, and yeah... they had 10mm of diameter and 14mm of depth to put in a serious allen or torx hole... and they chose to thread-lock in with a 5mmx5mm allen socket. Not their finest engineering moment :- ).

 

[Jeremy R.]

At least Saab didn't use a pair of Phillips head screws like Honda did on their older cars. I've always had good luck getting the Saab ones out with an impact driver, but the Phillips screws strip too easily for even that. I always thought it was weird that the rotors on my parent's Pontiac Grand Prix weren't held on by anything but the wheel, but it worked, and there were never any issues getting the rotors off. Of course that car also had studs, which allowed the rotor to sit on the hub a little more securely while the wheels were put back on.

 

[jvanabra]

They used Philips screws back in the '80s I'll tell you what!

 

[jvanabra]

Definitely not hardened, I've had to drill out several. Friggen insane choice of fastener in that environment.

I don't think it's Saab, I think it's mechanics. That screw goes in finger tight. It's just there to position the rotor, and it can't go anywhere once the wheel is on. Put a little anti-seize on it then turn it in with a screwdriver and it'll probably come out with one. I think you get these impact wrench jockeys who hammer on it and then you've got an issue.

 

[Jeremy R.]

The factory torque spec for that screw is very low. When I tighten mine, I just use a hex bit and my fingers. I don't use a ratchet or a screwdriver handle. I also use anti-seize, of course.

 

[BobSaabit]

But the factory loctite-ed them in, too. Taking out originals was always more of a chore than it needed to be.

Anyway, got this one out. I'd rate them as moderately hard steel. I had my small selection of cobalt drills and they did OK... the final cut was at 1/2" to remove the remaining collar with a titanium coated drill that was previously unused. Kept a steady flow of oil as I drilled, minimum speed... not too bad.

 

[jvanabra]

Are you certain they were thread locked? I have never seen that on a 9-3 and they were positively not on the c900 or 9000. There would be no reason for that. Thread lock is used on very few parts... virtually no chassis parts.

 

[BobSaabit]

They definitely were on the NG900, although that's the only one of these I owned with original rotors. I recall other DIY's observing the same thing at the time.