Does Using Antiseize On Bolts Cause One To Overtorque Them?
 

Hello:
As a newbie I wish to have someone correct me if i am wrong. I recently performed a repair and placed antiseize compound on rear hub mounting bolts prior to using my torque wrench to spec ft/lb. I am trying to think this through, and with the lubrication effect of the compound (I now realize I shouldn't use any compound on torque bolts, right?) on the threads if I tighten them to spec levels I will actually be overtightening them, right? My thought is I will have to overtighten to gain the necessary friction to trip my wrench. I am asking because I am now wondering if I should remove the bolts, clean them up, and replace without compound. Thanks for your insight and experience!

Michael

Hi,

Hopefully others here will correct me if I'm wrong, so take this with a grain of salt.
It's my opinion that anti-seize may be overused by some.
I tend to only use it where absolutely necessary (e.g. exhaust bolts, where two metals are involved like steel threaded spark plugs in an aluminum head). I'm not sure if it is needed for hub bolts or not.

There is a coefficient of friction calculation involved when torquing a bolt properly.
You might want to check out this article that explains this to some degree.

UPDATE:
http://www.mechanicsupport.com/bolt_torque.html addresses anti-seize in particular and indicates caution when using it to prevent over torque.

I learn something every day ... good question Michael

What I get from this is to use anti-seize only where the manufacturer specifies it's use.
It appears that when using anti-seize you are more likely to "over torque" a bolt so I don't think you want to compensate by tightening any further.
I suppose only a Toyota shop manual would have which bolts need anti-seize but you might be able to call a Toyota certified shop and find out about a particular bolt or set of bolts.

If you cleaned off as much compound from the bolt threads as possible doubt the clamp up values obtained will make much difference. I personally would not redo the job but if concerned clean the bolts and nuts with solvent and let them dry before reassembly. Why worry.

Keep in mind most people never use a torque wrench the result being over or under torqued bolts, rarely is this an issue unless its a critical location.

Antiseaze compound is good for press fits where there is a chance over time two parts will fuse together due to corrosion. Or if a fastener was difficult to remove the first time and don't want the second time to be equally as difficult.

Unless specified in the repair manual, the fasteners are dry.