Question 68 of 140

Is a trailer built before ABS was required legally allowed to be retrofitted with an antilock system?

Pick an answer

Yes, retrofitting is possible and can be a worthwhile safety upgrade even though it isn't required on older trailers
No, ABS can only ever be installed at the factory during manufacture and never added afterward by a repair shop
No, only tractors can have ABS added after manufacture
Retrofitting is illegal under any circumstances

Correct!

Not quite. The correct answer is highlighted.

Show answer

Correct answer to question 68 (Combination Vehicles): Yes, retrofitting is possible and can be a worthwhile safety upgrade even though it isn't required on older trailers

Why

Older trailers built before ABS requirements took effect can still be fitted with the system afterward, and while it isn't mandatory on them, it can meaningfully improve braking safety.

Updated: November 2026

Get ready for the knowledge testFree for iPhone and Android

Practice it in test 230 questions · pass with 24 (80%)

Is a trailer built before ABS was required legally allowed to be retrofitted with an antilock system?

Why

More questions from this subtest