let me make a suggestion. if the ramp is full width with steel mesh... and you can get away without need of the ramp... remove the ramp.
i have a 6.5-ish by 15'-ish dual axle trailer that i have towed with all of my vehicles. the ramp catches alot of wind and it is VERY apparrent behind my JK. Even my Tahoe downshifts all the time with the ramp on it... particularly when there are strong winds.
otherwise, keep the overdrive off (if auto) and drive on. my JK is an auto and wont haul with the O?D on. i think it is a little harder to put a tranny cooler on the JK since it has all metal lines. you have to either cut the line(s) or find matching connectors. i didnt inspect real hard, but i didnt see the usual rubber line on the return side.