Rotor Hub Screw - Torx? Stripped?

[kirkhilles]

Hey guys,

New-to-me-2014 with 106k miles and I'm doing an obviously way-overdue brake service. One wheel went fine and I was able to replace the drilled/slotted rotors with an more appropriate Centric rotor and Brembo pads.

But, on my other front rotor there is a retaining screw (see picture). Is this possibly an OEM screw? I'm assuming not. Any idea what size it is? Does it look stripped? Will I need to drill it out? I am replacing the rotor, so I don't care about damaging it (nor the screw obviously) but don't want to damage anything else.

Is it a Torx screw? If so, what size?

 

[kirkhilles]

I got an assortment of Torx screws and I'm glad I did as it was an oddball T45 Torx. I'm assuming that this is not the factory screw (on the Model 3 it appears to be a 10mm socket which makes far more sense) and that whomever installed the slotted/drilled rotors (which makes zero sense to me on a Tesla unless you are planning on tracking it) put it on there.

 

[TonyT]

That's factory and looks ok, sounds like all your others are missing.

 

[CorneliusRox]

Go to an auto parts store and buy a set. A full set is ~$30 at O'Reillys.

Those fasteners are only there for manufacturing anyways. It keeps the hub assembly and rotor together prior to it being installed on the vehicle.
In some very rare cases it can be there to control balancing, but not in Tesla's case.

 

[Typhoon43]

Definitely get a set of T-15-T55 bits and then save yourself the murderous rage and aneurysm inducing feeling when one of them DOES start to strip or rust in place and get an impact hammer. This thing saved me after a 2 days wrestling match with a steering wheel replacement, and then when it came time to help my buddy with a rotor job on his Benz because "there's some stupid star screw that won't come out", I just maniacally giggled and whipped this bad boy out. One whack and we were golden. It uses simple math to undo stuck bolts and screws. It turns RAGE into TORQUE. These things are lifesavers:

MANUAL IMPACT DRIVER

 

[CorneliusRox]

Definitely get a set of T-15-T55 bits and then save yourself the murderous rage and aneurysm inducing feeling when one of them DOES start to strip or rust in place and get an impact hammer. This thing saved me after a 2 days wrestling match with a steering wheel replacement, and then when it came time to help my buddy with a rotor job on his Benz because "there's some stupid star screw that won't come out", I just maniacally giggled and whipped this bad boy out. One whack and we were golden. It uses simple math to undo stuck bolts and screws. It turns RAGE into TORQUE. These things are lifesavers:

This, but also get yourself a set of reverse drill bits, and a can of MAPP gas. There's not much you can't tackle with that combo.
Also, since we're talking about German cars, make sure you get a set of 'triple squares'. Those aren't torx or allen's! ;-)

 

[ngng]

Never understood why they have that retaining screw with studs

 

[CorneliusRox]

Never understood why they have that retaining screw with studs

It's specifically for manufacturing. They like to do things in sub-assemblies before the car comes down the assembly line, or even at a Tier 1 supplier. That screw holds the rotors on before the hub assembly goes onto the car. It's really pointless to keep it on outside of the assembly plant.
It'd be a toss up if the mass of the screw was accounted for in the rotating assembly analysis or not. I'd guess not since wheels seem to have way more equivalent mass tolerance than that fastener would ever have.