FORD 2013 E-450 v.2 - Manual (Page 283)

On all two-piece flat wheel nuts, apply one drop of motor oil between the
flat washer and the nut. Do not apply motor oil to the wheel nut threads
or the wheel stud threads.
Note: Inspect the wheel pilot hole
and mounting surface prior to
installation. Remove any visible
corrosion or loose particles.
282 Wheels and Tires
2013 Econoline (eco)
Owners Guide gf, 2nd Printing, November 2012
USA (fus)