I'm moving up from a Ram 2500 diesel to a 3500 also diesel std bed SRW. I'll be pulling a Solitude 310GKR, GVWR-15,000 and hitch weight 2350. I can't decide between the 6.7 turbo diesel, 6 speed or the 6.7 HO with the aisin transmission. Who has experience with this and also what gear ratio? I know the higher gear ratio gives you more towing power and better acceleration but mpg goes down. Also the HO is a heap more money and more expensive maintainence. The HO gives you 3230 more pounds of towing capability but 170 pounds less of payload. I need help to make this decision. Thanks