An Anti-Lock Braking System (ABS): Question An Anti-Lock Braking System (ABS): Answers Is not available for most trucks. Is not helpful in most situations. Is required on newer trucks. Explanation Beginning between 1997 and 1999, most commercial vehicles, trailers, and dollies are required to be equipped with ABS. This questions appears in the following tests: Iowa Tank Louisiana Class A Knowledge Test Nevada Class A Knowledge Test South Dakota Tank Wyoming Tank
