I want to change my lower ball joint on my 850. I can get the three 13mm bolts in row off but I can't get "pinch bolt" out that fastens the ball joint stud to the steering knuckle.

I tried penetrating oil, putting an impact wrench on the bolt's head and vibrating the heck out of it, opening the relief slot, and air hammering the whole general area; nothing seems to make it budge. I live in Minnesota so everything under there is pretty rusted.

I have seen a lot of write ups on Audi and VW forums discussing these notorious "pinch bolts" especially a four inch one on their upper control arms. The Volvo does not seem quite as daunting but its the same thing: trying to laterally slide a highly corroded bolt that has been somewhat bowed by tightening around a hardened steel ball joint stud.

Has anyone had any experience with this?

 

They are a real PITA to get out.

The way I deal with mine is to get the nut off which is relatively easy and then lay on the bolt with an impact wrench while tapping the back side with a hammer. I use a long extension on the impact wrench to get a good angle on it with the steering wheel turned.

It will break free and then spin in the steering knuckle and after it starts spinning it is fairly easy to drive it on out with a punch. I think the worst one I dealt with was from my son's car that I bought in Chicago. They must coat the roads with battery acid after a snow storm.

Your next problem will be to get the ball joint out of the steering knuckle. Some folks just have the Midas touch and they can give it a little tap with a hammer and it will fall out. On all of mine I have had to beat the crap out of it with a pickle fork to get it to release.

...Lee