Ford econoline e350 2015 Owner's Manual page 241

240
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.
2015 Econoline (eco)
Owners Guide gf, 2nd Printing, December 2014
USA (fus)
Wheels and Tires
Note: Inspect the wheel pilot hole
and mounting surface prior to
installation. Remove any visible
corrosion or loose particles.