Home › Practice › Doubles & Triples › Question 39
When uncoupling, the proper position for the trailer landing gear/dolly support is:
Correct answer: B. Lowered to firm contact and crank handle secured
Why: Lower landing gear to firm contact with the ground (not full weight on it; the fifth wheel still bears load until release) and secure the crank handle.
Each additional articulation point multiplies rearward amplification. A driver pulling triples must steer earlier, brake sooner, and inspect twice as much equipment as a single-trailer driver.
Learn the correct trailer placement order by weight, the procedure for converting a single to a double, and the special inspection items unique to converter dollies and pintle hook assemblies.
The Doubles & Triples portion of the CDL knowledge exam covers more than this single question. Use this site's full Doubles & Triples bank to drill every topic, then test yourself with one of our state-specific practice sets to confirm you are ready for the actual DMV exam in your state. Always check your state's CDL handbook for any local addenda before the test day.
If you are still building your overall CDL foundation, start with the General Knowledge bank — every CDL applicant must pass it — and then work outward to the endorsements you plan to add.
