There are 4 main stud hole types which are identified as follows:
- American / Japanese R22 Ball Taper for Double Cap Nut
- English 80 degree Countersink
- ISO No Countersink for Two-Piece Flange Nut
- DIN R18 Ball Taper for Nut & Washer
Note: When retro-fitting forged alloy wheels in place of steel wheels on some truck models (e.g. Hino & Isuzu trucks), a special retro fit forged alloy truck wheel, with a 10/335 bolt pattern and a 32mm Retro stud hole size is required.
Matching retro wheel nuts are required for this application.