[vilord]

So the retainer bolt on one of my front brakes was completely seized in the threads.

Rather than driving about with one new front brake and one with 1/16" left on the pads while pondering how to get it out, I decided to just drill it.
But now, I don't have a retainer bolt, and even if I did, the bottom of the bolt is still seized in there.

Do I care? It will be annoying when working on the brakes or when changing wheels if the disc comes loose, but... other than that I can just ignore it, right?

Right?

[Emilime75]

All it does is keep the lug bolt holes lined up...aside from a little aggravation when installing wheels, nothing to fear.

You could drill out the center of it and try an easy-out, or drill and tap...

[vilord]

[geko29]

Yeah try a screw extractor. They don't always work, but work more frequently than you'd think.

[david in germany]

I came from Toyota to bmw. My old celica had a very similar brake setup but lacking the retainer screw. Never an issue because the caliper always holds the rotor in place.

[vilord]

Same, I was running a 2002 Celica GT

I'll order up a set of screw extractors and 4 new rotor holding bolts. The other three are fine, but the hex hole is a bit worn out from 12 years in New England salt.

For now, though I'll just drive it!

[Efthreeoh]

I'm not sure about the Toyotas, but the few I've dealt with have wheel studs vs. BMW's wheel bolts, so the rotor on the Toyota self-locates over the studs, does it not?

Vilord, the rotor retaining bolt threads through the hub flange, so remove the caliper, rotor, and hit it with some penetrating oil and drill out the bolt shaft. It may start to thread through the flange. But, based on my experience, the rotor will soon rust in place and not be a problem... maybe. If the wheel seizes to the rotor, as they usually do, then it's PIA time.

When I do brakes on a BMW, I always buy new rotor bolts, they are cheap. I also coat the threads with anti-seize. The torque spec is only around 15 lb.-ft. People tend to torque the living crap out of the rotor bolt for some reason; like it is holding the entire wheel on the car

[vilord]

Yeah, the shop that installed the last set of front brakes 4 years ago definitely over-torqued those bolts. I added anti-seize to the one I was able to remove and made it just tight enough to not fall out. I'll add 4 new ones to my shopping list so when I do the rear brakes in the spring I remember to replace all of them.
I also added some anti-seize to the mating surface between the wheel and the rotor, so hopefully the wheel won't seize to a loose rotor.

[david in germany]

When I install mine I have a little 1/4 ratchet and tighten it just hand (light) tight. Just enough that the rotor doesn’t wobble.