We had the same problems with a class C version of your coach. After, helper springs, air bags, steering stabilizer, completely insulating the cab with hush mat and new carpet and pad and even aluminum rims it still was too noisy and handled poorly. We traded it for a DP. Air brakes, air ride, engine in the back makes all the difference. We had our DP in 50+ gusting winds pulling our boat, in the mountains and it was much more stable. That is before you factor in the vastly better fuel economy. The poor v10 got terrible fuel economy in mountainous terrain. When towing it was worse. DPs are not nirvana they float across the roadway so don't expect sports car handling.