the snowmobile trailer no issues, the travel trailer you need to see what its actual weight is...
i am not trying to be a tow nazi, cause i hate them... but if your looking into a diesel you might as well make sure either you need it or dont need it. as others will say, if its 8000lbs then you add propane, clothes, the kitchen sink, a few neighbors, 3 optima yellow tops, and i guess 3 220 lb passengers ( kids, wife, and a few steaks to grill or somethin, im still unsure about the passenger weight tossed out there in towing figures) then you will be overweight lol...
at least your looking at diesel vs tunder and not gasser 3/4 vs tunder, cus the gasser only has higher weight capacity in the rear, and not really any more towing power at all, most likely less.
but i think it would do fine with less initial cost vs diesel and wayy less maint cost ( diesel oil changes alone can easily total 100 bucks depending on what oil u run, plus fuel filters... and the fact that due to emissions and exhaust fluid and....... diesels arent cheap anymore to operate)