SRW traction versus a DRW

Thank you for all of the replies my current truck 2013 f350 srw with locker and 4x4. Not a problem at all as many said just dip it into 4x. But when going down hill if at all over 60 the trailer will push the rear end of the truck back and forth. I'm currently running vision heavy hauler wheels with Toyo m110. This truck also seems to need to go to the shop ever 6 months for some electrical or fuel related issue. Looking to upgrade to a bigger rig when warranty is over. If I'm buying again might as well get back into weight limits. Right now the scale has the truck with 7,800 lbs on the rear axle. Correct sportchassis or similiar for the money I'm thinking I want out of the big 3 and go with the heavier rigs of freightliner, international, kenworth or similar 26,000 gvw rig.