[Kkuba]

Originally Posted by JBT2

Hmmm...it's difficult to figure out without seeing the assembly. Maybe your first idea of removing the two torx screws might be best. At least it "looks like" you might be able to jiggle the motor and drive cable(s) out of the track(s) to get them re-aligned.
Can you take a plasticine impression of the torx bolt head to determine what size torx driver you need?

I agree, I think removing those torx is the correct way forward.

The tool shop I called suggested I take measurements of the head itself, and bring those in. I tried taking some measurements, but I'm a bit sceptical of this, as when I took some measurements with a vernier caliper, I got different readings every time. As it depends on how deep you insert it, which 'gap' you are measuring (between which teeth). The differences in this dimension are so minuscule at this scale, it feels like a fruitless effort.

I checked against a dimensions chart for torx bits, but I could only find a chart with increments of 5 in that range, and so some measurements I took were just a bit larger than a T40, others a bit smaller than a T45, so it didn't really help me narrow down which one I need.

I considered calling BMW and asking what they would use, but I'm fairly certain that this is not a serviceable part, as the entire seat rail is sold as one assembly. And so they would probably not even touch it.

Originally Posted by RadiuM

If you have a 1/4" / 3/8" socket set, id recommend getting a set of these.

https://www.kincrome.com.au/torx-set-tamperproof-11pce

From memory they were about $30 from Bunnings, and along with a set of e-torx you can pretty much undo almost everything on the car.

Thanks for the suggestion, but I already have all of those sizes of torx, and none of them fit correctly.

The T40 fits very loosely, and I have been tempted to give it a go, but it feels like it is fastened very tight, and with so little engagement with the teeth of the T40, I am worried I will strip the screw, then I will be screwed. So I've resisted the urge to push on it any more than I have already.

I never thought it would be so challenging to find the right tool for the job.

The only other thing I am thinking is trying to find another T45, in case this one I have has a manufacturing defect, and is oversized.