[HighlandPete]

Originally Posted by Cisitalia

Looks like Pete beat me to it while I was typing. Good answer Pete and thanks for the corroboration.

You added a bit more depth to the subject, was trying to keep my comments simple.

Many just don't understand torque, let alone wet and dry values, and I mean tyre shops as well. I've seen the guys using a torque wrench and after setting the value, then proceed to apply more force past the setting....

HighlandPete

[CE750Jockey]

[quote=Cisitalia;13123278]

Originally Posted by CE750Jockey

Great question. You really should not be using anti-seize on the wheel lug bolts or caliper bolts. The design torque specification is always with dry fasteners. If you use the dry value torque specification with anti-seize applied, it acts like a lubricant and results in over torqueing of the fastener. Because of this it is possible to exceed the yield strength of the fastener or as a minimum stretch the fastener prematurely or excessively.

If you must use anti-seize, then you need to back down the applied torque by about 20-40% of the dry fastener torque specification.

Don’t use anti-seize on these types of bolts and torque them to the manufacturers recommendation (which defaults to dry values when not specified). Wire brush the bolts if looking a little bad and if really bad you can run an ez-out through the bolt holes to clean them up as well.

Keep in mind wheel lugs that are used on/off many times over the years should be replaced periodically. Also note worthy is, some manufacturers recommend replacing the brake caliper bolts every time they are taken off. Yeah but not many of us do that, but it is certainly a good idea to replace them every once in awhile. That is another good reason not to put anti-seize on brake caliper bolts.

In some applications when it is allowed to use wet or dry conditions, the manufacturer will provide both torque specification values. When the manufacturer designs a fastener application they typically pick a torque value about 80% of the ultimate yield strength of the fastener. That value is typically a dry value with no lubricant or anti-seize. So the wet value will be typically about 20-40% less torque. So you can see it is entirely possible to exceed the yield strength of the fastener with anti-seize, unless you reduce the torque.

Whoa! Thanks guys. I always learn some stuff from these forums. I had no idea.

[Cisitalia]

[quote=Efthreeoh;13123298]

Originally Posted by Cisitalia

Cisitalia, this is excellent advice and spot on. I would also point out that even with using anti-seize it is about impossible for human, even using a very long torque wrench; to physically have the strength to over-stretch a BMW wheel bolt. In fact the real danger here would be over stressing the chamfered bolt hole on the wheel and possibly cracking the aluminum wheel at a critical location as the hub area.

Thanks for the comment. I do agree BMW does use some pretty stout bolts. But I have seen other manufacturers that are not as good, so the caution would be more important. That said, we should still not be using anti-seize on BMW bolts either. They will fatigue over time with numerous on/off occurrences, so it is wise to heed the warning and periodic replacement of the bolts. I know this is particularly important to people who track their cars with the extra punishment they take and frequent wheel changing’s. I know this is contrary to BMWCCA Roundal contributor Mike in the technical section. Remember “Mike’s old school maintenance” and he believes in putting anti-seize on the lug bolts. I will someday respond similarly to him on this topic.

[Cisitalia]

Originally Posted by HighlandPete

You added a bit more depth to the subject, was trying to keep my comments simple.

Many just don't understand torque, let alone wet and dry values, and I mean tyre shops as well. I've seen the guys using a torque wrench and after setting the value, then proceed to apply more force past the setting....

HighlandPete

Thanks Pete. Being an engineer we get a little carried away some times and can't shut up.

Yeah the thugs over using the torque wrench is a problem. Can't trust many and that is why I watch every movement they make when I have wheels/tyres changed at the shop.

[CirrusSR22]

FWIW,

The BMW TIS has historically said you SHOULD coat the wheel bolts in a thin layer of engine oil. Both the threads and taper. That's the case for cars as new as the E46 and E60 at least. Haven't seen the E90 or F30 though.

Quote from the TIS.

Do not apply oil to new wheel bolts.
In the case of used wheel bolts, apply an extremely thin coating of engine oil to the threads and tapers before reinstalling them.

http://tis.spaghetticoder.org/s/view.pl?2/06/76

Brand new bolts presumably have a lubricant coating on the from the factory.

I dip the threaded portion into oil and then lay them on a paper towel for a few minutes. That wicks away most of the oil and leave a thin coating. I also dab a single drop of oil on the wheel's bolt hole taper.

[Elk]

Very interesting. Thanks

[AntBabeee]

All this is very interesting. THANKS A LOT GUYS I LEARNED A LOT!!! Better understanding now on what it is.

[Dudeonthego]

Same thing happens to mine... I think it's normal.