The reverse chain (not a gear set) can be a weak link. Just don't pull and yank on stuff in reverse, and you likely will never have an issue. The problem is if you don't know this ahead of time, abusing it in reverse can cause the chain to break, which can then snowball into an expensive transmission if not careful. If you need to pull on something, tie it to the rear and pull in L. Use your winch (if equipted) to pull yourself and your load forward instead of hooking your winch to what you want to pull and then using reverse.