Wheel & Rim Identification

Identification Required
by FMVSS120

Tubeless Disc Wheel

Two-Piece Rims  

Federal Motor Vehicle Safety Standard (FMVSS120) was issued in 1977 requiring that the rim size and type must be stamped on the rim and rim components (20” x 7.50” LW).  Prior to this regulation, the part number was stamped on the rim or rim component (B7520LWD).

This FMVSS120 rim- stamping standard also requires the following:  name of manufacturer, country where the rim or component was manufactured, date manufactured, the DOT symbol, and a designation that indicates the source of the rims dimensions (T=Tire and Rim Association).

Beginning in January 1989, Hayes Lemmerz identification stamps are located on the weather side of the rim under the tire bead seat.  

In addition to rim stamps, the following stamps are present:

· Wheel Part Number
· Shift and Date of Assembly
· Maximum Load (lbs.)
· Maximum Inflation (psi)

 Two-piece truck rims have the rim base size and type located as shown on inside diameter, or weather side, of rim base adjacent to the butt weld area of the rim base.  Side ring size and type are stamped on the outside face 2” to 4” left of the split in the side ring.

Tubeless Drop Center Rims Tube-Type Disc Wheel Three-Piece Rims

Drop center rims have the rim size and type stamped on the weather side of the rim base as shown:


 Wheel part number, maximum load and inflation, and assembly date are stamped on the exposed side of the rim fixed flange.

Three-piece truck rims have rim base size and type stamped on the inside diameter, or weather side, of the rim base, as shown, adjacent to the butt weld area of the rim base. Side flange size and type is stamped on the outside face of side flange 2" to 4" to the left on the butt weld area of the flange. On some types, the split lock ring has the size and type stamped inside of the ring and cannot be seen when mounted. The stamping is located on the flat face as shown, adjacent to the pry bar notch, away from the split lock ring.