§393.48 Brakes To Be Operative

Question 1: If a CMV manufactured on or after July 25, 1980 (see §393.42) has brake components on the front axle, and the brakes are not operable, does the vehicle comply with §393.48?

Guidance: No.

Question 2: If a truck or truck tractor manufactured prior to July 25, 1980, and having 3 or more axles, has inoperable brakes on the front axle or some of the brake components are missing, would the vehicle be in violation of §393.48?

Guidance: Yes. §393.48(a) requires that all brakes with which the vehicle is equipped must be operable at all times. Although §393.42(b)(1) provides an exception to the requirement for brakes on all wheels for trucks and truck tractors with 3 or more axles and manufactured prior to July 25, 1980, the exception does not affect the applicability of §393.48 for those cases in which the vehicle is equipped with inoperable front wheel brakes or only has certain portions of the front wheel brake system (e.g., shoes, linings, chambers, hoses) in place.

Question 3: Are the brakes on a vehicle towed in a driveaway- towaway operation or towed disabled vehicle required to be operable at all times?

Guidance: §393.48(c) provides an exception to the requirement that brakes be operable at all times. This exception covers disabled vehicles being towed and vehicles towed in a driveaway-towaway operation.

The driveaway-towaway exception in §393.48(c) is contingent upon the conditions outlined in §393.42(b)(2). Towed vehicles must have brakes as may be necessary to ensure compliance with the performance requirements of §393.52. A motor vehicle towed by means of a tow-bar when any other vehicle is full-mounted on the towed vehicle, or any combination of motor vehicles utilizing 3 or more saddle-mounts, would not be covered under the exception found at §393.48(c).

With regard to the disabled-vehicle provision of §393.48(c)(1), the combination vehicle would have to meet the applicable performance requirements of §393.52.