I will give you a different suggestion. It is very cheap, and can help with the chucking. I started driving class 5, in 1985 and we often moved partially full tube trailers. They had a very lively ride. I am still driving my first 5er from 2011, and it has a very light pin weight, only about 12-15%, even with a truck spare in the basement (it is a RK model). I pull with an el cheapo drawbar hitch, because simple is best. To help with the chucking, drive as smooth as silk, no cruise control, look ahead and think ahead. Brake smooth, time lights, make no sudden moves. At first driving like this will wear you out, until it becomes the way you drive all the time. It can make a big difference. This is not my idea, it was taught at the Dowell Schlumberger driving school in Tulsa and it does work.
