Wheel Fitment


There are four major areas to confirm fitment of Alcoa aluminum wheels with any particular hub/wheel combination: 1. Wheel mounting surface, 2. Clearance with other wheel end components. 3. Pilot bore fitment (hub piloted mounting systems), and 4. Stud standout (thread engagement).



Do not exceed maximum wheel load and/or  the maximum tire load rating. Fitment recommendations are for REFERENCE ONLY. Customer must compare OEM vehicle load rating to maximum wheel load rating. Refer to tire manufacturer's recommendation for proper tire pressure. Do not exceed the maximum cold inflation tire pressure marked on the wheel. Before mounting the tire, perform a wheel fitment check to ensure proper clearance from any obstructions.




  1. Remove one front wheel.
  2. Clean the mounting surface of the hub with a wire brush and remove any retainer (spring) clips.
  3. Hold the wheel on the hub and check for a flush mount. The mounting surface of the wheel must fit flush to the hub mounting surface. The backside of the wheel must not rest against any obstructions, such as the brake caliper, suspension components, balance weights, rivets, etc.
  4. Confirm pilot bore length is sufficient for hub piloted dual rear wheels. (SEE PILOT BORE LENGTH)
  5. Install three lug nuts and hand tighten. Rotate the wheel and turn the steering column fully in both directions to ensure clearance from any obstructions.
  6. Confirm stud standout is sufficient. (SEE STUD STANDOUT)
  7. Repeat steps for rear wheel as they apply.


PILOT BORE LENGTH (Hub Piloted Wheels)
Specify only hubs that are designed for aluminum hub piloted wheels. Hubs designed for steel hub-piloted wheels may not have sufficient pilot length to locate dual aluminum wheels.  (Measure the hub pilot to make sure the hub has a minimum pilot length that allows no less than 5mm for the outer wheel excluding the beveled edge.)  Before final mounting of hub-piloted wheels, lightly coat the wheel pilot or hub pads with a non-water-based lubricant, such as Freylube or equivalent, to minimize corrosion build up. DO NOT LUBRICATE THE FACE OF THE WHEEL OR THE HUB. 



Stud standout is the length of the stud from the wheel-seating surface (hub or brake drum) that penetrates the wheel and engages the nut.  This will dictate the amount of thread engagement obtained with any particular hub,/drum, wheel and nut combination.  For 5-, 6- and 8-hole cone seat wheels (Figure 1) the minimum thread engagement (length of stud threads in the cap nut) is equal to the diameter of the stud (approximately 10 full turns of hand tightness).  For ball seat and flange nut mounted wheels most states have laws which dictate full thread engagement or thread engagement past the nut body. (Figures 2 & 3)  Ensure that you know the laws for the states you operate and comply. Depending on the standout, inner steel and an outer aluminum wheel may be required for specific applications.  In some cases Alcoa provides alternate mounting hardware that can be used to replace the stock mounting hardware thus allowing the use of 2 aluminum wheels in the dual configuration. Please see the Alcoa wheel fitment guide or M-Series™ specification guide.




Alcoa axle covers for 16x6 and 16x6.5 dual wheels can only be used with Alcoa lug nuts (P/N 139987 and P/N 139698). These are not push-through axle covers.

Do not use OEM cap nuts with Alcoa axle covers.

For Alcoa ball seat wheel applications refer M-Series™ specification guide for vehicle application and proper mounting hardware kits.

Refer to your OEM for mounting instructions.  Refer to Alcoa service manual for additional mounting instructions.


Alcoa does not authorize, condone, or suggest the use of wheel adapter plates. Use only Alcoa recommended hardware on Alcoa aluminum wheels.



WARNING: Use of a wheel adapter plate with dualed Alcoa wheel assemblies can cause insufficient thread engagment of lug nuts on studs.


This condition can cause wheels to loosen and disengage from the vehicle, causing injury or death.


Never use wheel adapter plates with Alcoa wheels.



WARNING: Use of cap nuts that have chrome plating on the contact surfaces can cause reduced and inconsistent wheel clamping.


This condition can cause wheels to loosen and disengage from the vehicle, causing injury or death.


Never use cap nuts with chrome-plated contact surfaces. Use only recommended hardware on Alcoa aluminum wheels.