1. Regulations
  2. title 49
  3. chapter II
  4. part 230
  5. subpart C
  6. subjgrp 81
  7. § 230.112

View all text of Subjgrp 81 [§ 230.112 - § 230.114]

§ 230.112 - Wheels and tires.

(a) Mounting. Wheels shall be securely mounted on axles. Prick punching or shimming the wheel fit will not be permitted. The diameter of wheels on the same axle shall not vary more than 3/32 inch.

(b) Gage. Wheels used on standard gage track will be out of gage if the inside gage of flanges, measured on base line is less than 53 inches or more than 53 3/8 inches. Wheels used on less than standard gage track will be out of gage if the inside gage of flanges, measured on base line, is less than the relevant track gage less 3 1/2 inches or more than the relevant track gage less 3 1/8 inches.

(c) Flange distance variance. The distance back to back of flanges of wheels mounted on the same axle shall not vary more than 1/4 inch.

(d) Tire thickness. Wheels may not have tires with a minimum thickness less than that indicated in the table in this paragraph (d). When retaining rings are used, measurements of tires to be taken from the outside circumference of the ring, and the minimum thickness of tires may be as much below the limits specified earlier in this paragraph (d) as the tires extend between the retaining rings, provided it does not reduce the thickness of the tire to less than 1 1/8 inches from the throat of flange to the counterbore for the retaining rings. The required minimum thickness for tires, by wheel center diameter and weight per axle, is as follows:

Weight per axle (weight on drivers divided by number of pairs of driving wheels) Diameter of wheel center (inches) Minimum thickness (inches) 30,000 pounds and under44 and under1 1/4Over 44 to 501 5/16Over 50 to 561 3/8Over 56 to 621 7/16Over 62 to 681 1/2Over 68 to 741 9/16Over 741 5/8Over 30,000 to 35,000 pounds44 and under1 5/16Over 44 to 501 3/8Over 50 to 561 7/16Over 56 to 621 1/2Over 62 to 681 9/16Over 68 to 741 5/8Over 741 11/16Over 35,000 to 40,000 pounds44 and under1 3/8Over 44 to 501 7/16Over 50 to 561 1/2Over 56 to 621 9/16Over 62 to 681 5/8Over 68 to 741 11/16Over 741 3/4Over 40,000 to 45,000 pounds44 and under1 7/16Over 44 to 501 1/2Over 50 to 561 9/16Over 56 to 621 5/8Over 62 to 681 11/16Over 68 to 741 3/4Over 741 13/16Over 45,000 to 50,000 pounds44 and under1 1/2Over 44 to 501 9/16Over 50 to 561 5/8Over 56 to 621 11/16Over 62 to 681 3/4Over 68 to 741 13/16Over 741 7/8Over 50,000 to 55,000 pounds44 and under1 9/16Over 44 to 501 5/8Over 50 to 561 11/16Over 56 to 621 3/4Over 62 to 681 13/16Over 68 to 741 7/8Over 741 15/16Over 55,000 pounds44 and under1 5/8Over 44 to 501 11/16Over 50 to 561 3/4Over 56 to 621 13/16Over 62 to 681 7/8Over 68 to 741 15/16Over 742

(e) Tire width. Flanged tires shall be no less than 5 1/2 inches wide for standard gage and no less than 5 inches wide for narrow gage. Plain tires shall be no less than 6 inches wide for standard gage and no less than 5 1/2 inches wide for narrow gage.

AUTHORITY: 49 U.S.C. 20103, 20107, 20702; 28 U.S.C. 2461 note; and 49 CFR 1.89.

CITE AS: 49 CFR 230.112