I think that the CV bolts come out when they aren't properly torqued.
Proper torque means they have stretched enough to generate tension that
will prevent them from working loose.

The spec is 33 ft-lbs.  When you are under the van working in cramped
quarters, limited range of motion, etc., it is easy to think you have
exerted enough force when you haven't.  I was amazed at the difference
the one time I got to loosen and tighten the CV bolts with the van on a
lift.  Easy to do with the van on the lift.

Use a torque wrench for this job always.
I have communicated via pmail with a number of people who have had them
come out and not one of them used a torque wrench to tighten the bolts.
The one time I found mine loose was after doing it by feel and "being
sure" that I had them tight enough.  Luckily I checked them again not
too long after the installation due to an experience with another van
and cured my error before any problem developed.  Have always used the
torque wrench on this since then.

Not only does the torque wrench get them tight enough, but it also
lessens the chance that you damage a bolt or over tighten and strip it
when trying to remove it the next time.

I think it is best to use 12 star type bolts rather than Allen head.
Never had a 12 star strip.  If you use Allen heads ones, don't reuse
them or at least don't use them more than two cycles of tightening and
loosening.

A 1/4" Allen head drive can be pounded into a stripped 6mm Allen head CV
bolt and get a stripped one removed.  Has worked every time for me.  Got
this from Ben Huot's website several years ago IIRC.  If you have Allen
head CV bolts, this is a 'must have' tool.

Sam
--
Sam Walters
Baltimore, MD

89 Syncro GL, Zetec Inside
85 Westy Weekender
85 Mercedes Benz 300D Turbodiesel - to become veggie oil powered

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