[PGSigns]

One of things that may be adding to the issues. The long hitch is adding leverage to the 850# you have at the ball and the hitch may be well over the 1000 it is rated for. A long drop hitch can reduce the capacity of the hitch as much as a 1/3. What weight raring are the rear tires on the 2012. A tire with a softer side wall for comfort does not make a good towing tire. Have you looked at moving weight around in the trailer to improve the balance? Shoot for 10% of the trailer weight. I am going through that now with the toy hauler I have. Not that my duelly cares I just dont like all the tongue weight.
Jimmy