I suggest you just hook up your trailer and try it out before altering the factory bars. The leveling hitch should take much of the bother out of towing. An anti sway hitch will do the rest if the leveling hitch is not enough.

Putting on a heavier bar in back might get you into oversteer when cornering.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.