[Cupp417]

Hey all,
I recently did my first autocross and came in 2nd in my class which I'm very happy about. However, it brought some things to my attention.

What is the lug nut size? I used a 21 mm but I tried an english size (forget which, may have been 13/16) and it worked as well. What is the actual size of the lug nut?

Second, what is the factory torque spec for the lug nuts? I did 90 ft-lbs for the race. Tech told me that is a safe level.

Thanks!

[shifter87]

I know mine is 13/16 so i would have to say 13/16 or 20-21mm as you used. Although I dont torque mine so i cant answer that question sorry.

[BKid]

21mm and 100 ft-lbs.

[Cupp417]

Thanks for the info!

[brenspeed]

We use a 13/16 and torque the lug nuts to 90 ft-lbs.

[Itchy]

Why is everything else on our cars metric and the lug nuts are SAE?

[pikapp]

Per Owners manual.

WHEEL LUG NUT TORQUE SPECIFICATIONS
Retighten the lug nuts to the specified torque at 500 miles (800 km)
after any wheel disturbance (tire rotation, changing a flat tire, wheel
removal, etc.).

Bolt size Wheel lug nut torque*
1⁄2 x 20 100 (lb.ft.) 135(N*m)

* Torque specifications are for nut and bolt threads free of dirt and
rust. Use only Ford recommended replacement fasteners.