Tractor Trailer, extendable links, wheels that move, etc

wondertoad
Sun, 09 Oct 2011 21:35:39 +0000
Auto Type/Class

I’m in the Pacific Northwest, and I often see double trailers linked by a long bar that extends and contracts with a safety light attached. Also, some of the tractors and trailers have wheels that retract up when not in use. What are the purposes of these thingies?

9 posts - 6 participants