Overview
Every motor carrier and its employees must be knowledgeable of, and comply with, the requirements of the Department of Transportation (DOT). No motor carrier may operate a commercial motor vehicle, or cause or permit such vehicle to be operated, unless it is equipped in accordance with DOT requirements.
Required Brake System
Each commercial motor vehicle must have brakes adequate to stop and hold the vehicle or combination of motor vehicles. Each commercial motor vehicle must meet the applicable service, parking and emergency brake system requirements. There are specific requirements for hydraulic brake systems, air brake systems, vacuum brake systems, electric brake systems and surge brake systems. Each commercial motor vehicle must be equipped with a parking brake system.
Wheels
Wheels and rims must not be cracked or broken. Stud or bolt holes on the wheels must not be elongated or out of round. Nuts or bolts must not be missing or loose.
Tires
Motor vehicles must not 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;
- Has a cut to the extent that the ply or belt material is exposed; or
- Has a cold inflation pressure less than that specified for the load being carried.
Any tire on the front wheels of a bus, truck or truck tractor must have a tread groove pattern depth of at least 4/32 of an inch when measured at any point on a major tread groove. Other tires must have a tread groove pattern depth of at least 2/32 of an inch when measured in a major tread groove. A regrooved tire with a load-carrying capacity equal to or greater than 4,920 pounds must not be used on the front wheels of any truck or truck tractor.