Pin Box again Moryde vs Trailair

I helped a friend install a trailair pin on his MS fifth. Towing home they had a lot of chucking and unhappy to have the air pin. Later he called and we were or I was thinking when the road made the fifth go up the lighter load let the trailer go back and when the load came down it on slowing down it went forward. Later he called from a mall parking lot after leaving the fifth at an rv park and figured because he had a bar style of hitch it has slop that would allow to do what we figured . It was adjustable and then no more chucking.

chevman