converter dolly
A fifth-wheel axle unit that lets one trailer tow another.
A semitrailer has no front wheels. The dolly gives it some. You hook the dolly to the first trailer with a pintle hook, then back it under the second trailer.
Also called: converter gear
Why it matters on the CDL test
Questions ask how to couple and uncouple the dolly, what trailer height is right, and how an ABS-equipped dolly is marked.
Appears in 40 test questions
See 36 questions on the Doubles & Triples testExample: You wheel the empty dolly by hand into line with the second trailer's kingpin before backing the first trailer onto it.
In other languages
- Español
- dolly
- Русский
- тележка (dolly)
- Українська
- візок (dolly)
Related terms
Where it comes from
- CDL manual, Section 7.2.1 (coupling twin trailers with a converter dolly)
- CDL manual, Section 7.1.8 (ABS on converter dollies)
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