I recently purchased a new TT that weighs 6800# dry. I am currently pulling it with my '99 F150 which does ok but I am going to be truck shopping early next year and am debating if I want another 1/2...
If you want to stick with a gasser, I think I'd try a GM 1/2 ton HD with the 6.2 and towing package unless you're thinking of changing up to a larger RV in the future. Then, I would go with a diesel. JMHO