(a) No motor vehicle shall be operated on any tire that has body ply or belt material exposed through the tread or sidewall; has any tread or sidewall separation; is flat or has an audible leak; or has a cut to the extent that the ply or belt material is exposed.
(b) Any tire on the front wheels of a bus, truck, or truck tractor shall have a tread groove pattern depth of at least 4/32 of an inch when measured at any point on a major tread groove. The measurements shall not be made where tie bars, humps or fillets are located.
(c) Except as provided in subsection (b) hereof, tires shall have a tread groove pattern depth of at least 2/32 of an inch when measured in a major tread groove. The measurement shall not be made where tie bars, humps or fillets are located.
(d) No bus shall be operated with regrooved, recapped or retreaded tires on the front wheels.
(e) No truck or truck tractor shall be operated with regrooved tires on the front wheels which have a load-carrying capacity equal to or greater than that of 8.25 x 20, eight ply-rating tires.
(f) No motor vehicle shall be operated with tires that carry a greater weight than that specified for the tires in any of the publications of the standardizing bodies listed in FMVSS 571.119 (49 CFR 571.119) and marked on the sidewall of the tire, unless:
(1) The vehicle is being operated under the terms of a special permit issued by the State; and
(2) The vehicle is being operated at a reduced speed that is appropriate to compensate for tire loading in excess of the manufacturer's normal rated capacity.
(g) No motor vehicle shall be operated on a tire which has a cold inflation pressure less than that specified for the load being carried.
If the inflation pressure of the tire has been increased by heat because of the recent operation of the vehicle, the cold inflation pressure shall be estimated by subtracting the inflation buildup factor shown in Table 1 from the measured inflation pressure.
Table I - Inflation Pressure Measurement Correction For Heat
Minimum Inflation Pressure Buildup
Average speed Tires with 4,000 lbs Tires with over 4,000 lb
of tire in (1,814 kg) (1,814 kg)
previous hour maximum load
41 to 55 mi/h 5 lb/in2 (0.36 bar) 15 1b/in2(1.07 bars)
(66 to 88.5 km/h)
(Ord. 97-10. Passed 11-5-97.)