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Old 10-28-2003, 02:04 PM
Kestas Kestas is offline
I told you so!
Join Date: Jun 2002
Location: Motor City, MI
Posts: 2,804
I've been paid good money to study fasteners and I work with people who write the specifications for wheel bolts. Duke is correct on all points. There is no hard and fast rule to cover every fastener you come across. Some head bolts are installed dry, some are dipped in oil. The manual should be specific for this type of work.

The trucking industry is instructed to place TWO drops of oil on each wheel bolt before installing and torqueing lug nuts. Antisieze compound is okay, but we've seen cases where it's dried out, more added, and has turned into a big crunchy mess. We've also seen cases where antisieze compound is slathered on every conceivable surface, raising clamp loads to alarming levels at specified torque. You've got to be reasonable about what you're doing.

Since I'm a big user of antisieze compounds, I asked a fastener engineer how my wrenching will affect clamp loads. He remarked that torque values should be dropped roughly 10% to achieve the same clamp load.

Torque values depend on variables such as grade, size, thread pitch, coating, and whether a fastener is cased, so it is difficult to come up with a on-chart-fits-all guide.
95 E320 Cabriolet, 140K
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