General Knowledge · Antilock Braking Systems
Under federal regulation, which of these vehicles must have antilock brakes (ABS) installed?
1.A truck tractor that was manufactured on or after March 1, 1997Correct answer
2.Only trailers, regardless of when they were manufactured
3.Only vehicles that are used to transport hazardous materials
4.No vehicle is required to have ABS; it is entirely optional equipment
Explanation
A truck tractor manufactured on or after March 1, 1997 is required to have ABS under 49 CFR 393.55, alongside other air-braked commercial motor vehicles built on or after March 1, 1998 and hydraulic-braked trucks and buses built on or after March 1, 1999. The wrong options each misstate who the rule covers: trailers are not the only vehicles required to have ABS, tractors and other power units are covered too, hazardous materials cargo has no bearing on the requirement, and ABS is not left to manufacturer discretion, it is a dated federal equipment mandate.
Source: 49 CFR 393.55(a), (c)
Related Antilock Braking Systems questions
- What does federal regulation require of trailers manufactured on or after March 1, 1998, regarding antilock brakes?
- What does antilock braking system (ABS) actually do for a driver?
- How should a driver apply the brakes on a vehicle equipped with ABS?
- If a vehicle's ABS malfunction lamp stays on after starting the engine, what should the driver do?