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<misc> re: re: lug bolts torqued!

<I often have my lug nuts tighten up by themselves so that I need a 2 foot
cheater bar on my socket wrench to unfreeze them. I *know* I torque them
correctly to ~85ft/lbs with a torque wrench, immediately after they are easy
to remove, but a month or two after and UGH!

Don't know why they freeze by themselves but they do.>

    I don't think they're tightening up, but they do "freeze" by themselves.
 It's galvanic corrosion occurring as a result of dissimilar metals in
contact with one another (steel lug bolts against aluminum alloy wheels).
 This corrosion can also make removing the wheel from the (steel) hub
difficult.

    I recommend a thin layer of anti-seize compound applied to both the hub
and the "shoulder" part of the lug bolt that contacts the wheel.  I do both
any time I remove the wheel.  I tighten the bolts to ~70 ft/lbs, and though I
have never had them loosen by themselves, you might want to recheck the
torque every couple hundred miles just to be sure.  If any do loosen, go
higher.  85 ft/lbs seems a bit tight to me, but I assume that's dry, without
the lubrication provided by the anti-seize on the bolt, so the actual load on
the threads may be about the same.

    Of course, for driver's schools, you should recheck the bolts just before
each run session, while the wheels are relatively cool.

    BTW, this stuff is also great on spark plug threads-- reduces chances of
head-thread damage.

Happy torquing,
Gary
'87 535i, '88 325is