Are these a must? I had to literally chip one off on the front left rotor. It was rust welded. Now I cannot replace the screw as the hole on hub is totally ruined. As the lug bolts ultimately hold the rotor in place, I was thinking I just go without one on this rotor.
Any thoughts will be appreciated.

 

What do you mean by.......I had to literally chip one off ?

Post a photo of this disaster.

 

Can you re-tap the hub hole?

Can you heli-coil the hub hole?

 

The head of screw was taken off bit by bit. Screw is of very hard steel.

 

I can. But I want to know if I can get away with not doing it. It takes a lot of time and work in my tiny garage.

 

have you tried heat? Usually my go-to for broken bolts when I try to back them out. ​​​​​​​​​​​​​​You are the one who makes the decision and my post is not a recommendation. Personally I would not worry about the retaining screw. The lug bolts are doing the real work keeping things together and in place.

 

Thank you.

 

When you tighten that little screw, the holes in the rotor hub are centered over the threaded holes in the wheel hub. Both the hole in the rotor and the screw head contact surface are tapered. There is no reason to assume the same thing occurs when you tighten lug bolts, as nothing about that process moves the rotor … or moves it with accuracy.

it’s only wishful thinking to consider the notion there exist non necessary parts.

In fact, Mercedes specifies the screw be replaced with a new one every time it’s removed. That’s because it is provided with preapplied thread locking compound. That’s a clue it shouldn’t loosen … or be omitted.