My car is in for it's first service this week (15 moths old, 23k miles) and when booking it in, I said can they look at the power steering as it started making a pigeon like squeaking noise a few months back.
Oh that will be the bushing at the bottom of the column, common issue on a 1er says service man.
Also I'd been getting a few CEL's that would cancel, so can they investigate that.
Next day, I get a call from them to say the CEL issue is the coil pack for No.5 cyl, but the part is on back order from Germany. Oh, we've fixed your steering, we've put a new steering rack on the car.
Thought it just needed a new bushing?
Aah, on a normal 1er with electric rack, but on the 135 with the hydraulic steering the bushing is integral with the rack and the whole rack needs to be replaced.....
A new rack is £1200 before fitting here in the UK .... that's just shy of US$2000
So, glad that was covered by the warranty.
So, if your 135 steering is making squeaky noises and is out of warranty, be prepared for a big bill.