Anti Seize or Grease on Ti Lugs and Torque?

Pre-tighten ti stud bolts: 25-45 Nm (18ft lbs - 33ft lb)
Final tightening of ti stud bolts: 100 Nm (74ft lbs)

 

I don't grease or use anti seize on my lug bolts and I have Ti bolts on 3 of my cars. These cars aren't my DD tho.

 

I believe if you put any kind of lubricant on the bolts, the torque values will be completely inaccurate.

 

I believe this is correct. You could over tighten the bolts.

 

Don't ever put grease or anti-seize on lug bolts.

 

As with most internet postings, it is sometimes hard to get a definitive/correct answer.

I did a Google search for 'anti-seize on titanium bolts' and found many people say put anti-seize compound on the threads. That said, I have been using Anti Seeze product on my titanium lug bolts for many years and will continue to do so. There may be good chance of galling and corrosion between the dissimilar metals.

I am waiting to hear back from a manufacturer of anti-seize products as to this lug bolt application.

to be continued...

 

Anti-seize, like most oily lubricants, increases the effect of any given torque applied to the fastener; my rule-of-thumb is by 25% but I don't recall where I read that.

Regardless, if you are applying the factory specified torque to a fastener with anti-seize, grease or oil on the threads, you are grossly over-torqueing the fastener and because of that are subject to a catastrophic fastener failures.

 

Lubricant applied to the threads and/or the interface between the lug nut and the wheel will increase preload for a given applied nut torque. The preload difference can be a factor of two or higher. So the posts warning against applying lube and using the unlubed fastener torque specification are correct; don't do it or you risk breaking the stud.

Thread lubricants are used mainly to prevent galling (seizing). The need for lube depends on the materials of the male and female threads. Some material combinations are fine unlubed, while others will gall without lube. If you've ever seized a fastener, you know they can be almost impossible to free. By the way, there are different types of thread lubes available and they can produce significantly different friction coefficients.

Bolted joints, including road wheels on vehicles, require sufficient preload so that the joint stays tight under all loading conditions, usually with some margin thrown in. The fastener number, size, and material and the assembly torque used in the joint are selected with that in mind. For critical joints, it is best to stick strictly with the manufacturer's torque and lubrication requirements.

 

One more point about over-torqueing the wheel nuts/bolts: if you have done that, you very likely have weakened the bolt. This means to get back to a safe configuration you need to replace all of them and then torque them according to the factory spec from then on.

 

I did a search for the manufacturer of my Ti lug bolts (Poggipolini) and find nothing of them, just places that sell them. I requested installation information by email and voice message to VividRacing as they sell this brand and I have bought stuff from them. Have not heard back yet.

 

FWIW I would not use anti-seize or grease on the lugs.

I would make sure the lug threads were clean though - maybe a tooth brush with WD and dry/ clean off the WD completely.
If you remove the lug nuts once a year and keep the lug threads clean I would doubt you will incurr a bonding beteen the different metals.

+1 for ramping up to final torque figure.