Just replaced my tow vehicle with a new to me 2013 Duramax RWD 3500, I had a 2006 Dodge Ram with the 5.9 Cummins, Well, the dodge bedrail sat at 55 inches tall the Duramax sits at 57 inches so what do...
Chance of some added chucking but your hitch will take care of that. One thing to consider: If the new truck's height is due to additional bed height (bed to rail) then you might run into clearance issues since you started with 5" to begin with. Do you air up your hitch higher for bed clearance reasons or just up to the towing line? I believe Trailersaver can supply you with mounting risers to raise your hitch if necessary.
Hope the new truck squats the right amount and you are good to go.