Do you use truck bypasses? Are trailers allowed to?

Often, when two major freeways merge, there are truck bypasses or truck routes. Once in a while, the signage says "all trucks and trailers must use bypass." Usually, it just says trucks, without mentioning trailers.

So that is my question -- is there any rule that prohibits travel trailers from using those bypasses? Assuming that there is no such rule, is it a good idea to use them?

Personally, I have found the bypasses helpful -- I can take the transition at a slower speed than the passenger cars are going, without fear of obstructing traffic.

Thanks in advance for your collective wisdom!