How to Install Ball Stud?
 

I am about to replace a few HLC's (ball studs) on a 1989 420 SEL. I've read the service CD as how the job should be done. I received the HLCs today and I see there is small plastic wire and tab, about the diameter of a toothpick protruding from the underside of the top flange. Should this plastic wire and tab be pulled out prior to installation? What's the purpose of the plastic insert?

Also I noticed that some of the old ball studs come up right away, and some come up slowly, like in a few minutes. Is the speed of the rise any indication of a defect?

Can one expect the service cd instructions to be complete?

Any and all recommendations are appreciated.

Thanks,
Joe

There should be a torque value on the CD for the ball studs. I dimly recall removing the plastic pieces when I did my 380 - I think that they keep the oil feed holes clear.

Steve B did a post where he described how they compressed new balls studs in a vice before installation to be sure that they got a quick and accurate pre-tension measurement. You might poke around for that post.

You were planning to use the special tool to pre-tension the new ball studs, weren't you?

Pre-tension
 

What's this about pretension. I didn't read anything on the CD about pretension. Please tell me all about pretension!

I was just going by the CD. Oil the threads on the new one, tighten to 60 NM, check it with the go-no-go guage, adjust the thrust washer.