Wheel Nuts

[jbcollier]

45 ft/lbs

It's based on the thread size: 3/8"x24 (UNF).  It all works well as long as you don't use an impact gun to install them.  Torque them properly and they will never fail.

[BDA]

This was a bit more interesting than I anticipated.

To my mind, the specified torque is determined by the size of the fastener and the S1 manual says to torque for a 3/8 UNF bolt should be 22 - 27 ft-lbs. It does not give a spec for the lug nuts at all. The TC manual also give s torque value of 22 - 27 ft-lbs. for 3/8 UNF bolts (why would it change?) but also says the 3/8 UNF lug nuts for the alloy wheels should be 40 - 45 ft-lbs. It gives no guidance for steel wheels that I could find.

I would use the 40 - 45 ft-lbs for steel wheels also. If the stud can take that torque for an aluminum wheel, it can take it for a steel one and 22 - 27 ft-lbs just seems too low.

[wilkrod]

All,
Issue resolved!
With the long shank nuts on the rears, and short up front, everything torqued to 40 ft/lb , no issues.
My car was born a T/C, but over the years it has acquired many "Special" components, rear brake cylinders as an example. So I don't know if this issue is a result of some unknown "Special" component necessitating the use of the longer shank bolts on the rear or what.
Many thanks to all who responded, and set me on the path to enlightenment.

[SilverBeast]

Glad you are sorted.