What happens when the wheels of a trailer lock up? Question What happens when the wheels of a trailer lock up? Answers The trailer will often continue to move in a straight line. The trailer may disengage. The trailer may swing around. Steering will become easier. Explanation A trailer may swing out and strike other vehicles if its wheels lock up. This is especially likely with lightly-loaded trailers. This questions appears in the following tests: Arkansas Combination Connecticut Combination New Jersey Combination Tennessee Tank