Planned a simple Saturday of replacing rear control arms on my E39 525i in anticipation of getting a needed four-wheel alignment Monday. 150k miles on the car, has a high-speed shimmy, no sense aligning it with old suspension parts (front arms, tie rods, and struts recently replaced, by me, without undue difficulty).
Start with the first bolt. Lousy access, but not impossible. It's tight. Real tight. Apply more force (as you do) - SNAP! Charming. It's a special bolt with an eccentric built in which is guaranteed to be A) only available from BMW, and B) not in stock at my local dealer on Monday. Lovely.
OK, maybe I can at least get everything else done so all I have to do is slap in the replacement bolt. Nope. Ball joint end of the arm just spins when I try to get the nut off. It's mounted horizontally, so I can't get a jack under it, and there's no good way to apply clamping or lateral force to it to stop it from spinning. And there's absolutely no way to get an impact in there.
Move to the other side. Same story. But wait, there's more good news! As I'm trying to maneuver things around and figure out if there's some magic perfect angle known only to German engineers, I feel play where I had not felt play before. What's that? Oh, look, it's the monster press-in ball joint that connects the knuckle to the lower control arm. The one I didn't order because it seemed OK when I checked it previously. And the one I don't have the tools to replace.
So now I've got a car that's undriveable due to the broken control arm bolt, that needs parts I can't get until next week, and requires additional work that would necessitate purchase of more tools. As mortifying and financially painful as it is to me, I'm giving up. It's going to my preferred BMW indy on a flatbed as soon as he can take it. I'm so ashamed. But I also know that the alternative involves me becoming enraged and smashing things, which will probably end up being even more expensive.
Maybe tomorrow I'll be struck by lightning or hit by a bus. It would be an improvement over today.
Rant over. I'm going back to my fetal position.