By going from 265/70/17 (31.8") to 35" tires you're are essentially reducing your rear axle ratio by 10%. From 3.73 to 3.38.
Looking at Rams towing chart going with a 3.73 tow rating of 10,350 to 4.10's increases it to 13,350. Assuming that reducing 3.73's by 10% your new tow rating would be 7,350lbs. If you tow less than that then all will be good.
JMO but I can't imagine a 2500 5.7 with 3.38 gears. Your mpg would take a big hit and towing power would be sluggish.
Remember too that your 1500 weighed considerably less than a 2500. And you already started out better with 3.92's over 3.73's.
If you had 4.10's in the 2500 it would be better.
