I have a 2012 Mega w/ DRD tunes,68, 120Kmi, and I just bought a 5th wheel.

I believe it has a 3in lift and 35's.

I know I need to re-gear, it currently has 3:42, probably going to 4:10.

The 5th wheel has an 11.2K dry weight, and the 4:11 rating is above 14K, so it should work beautifully.

I also have the Air-Lift 7K setup.

I am also looking into the Power Stop brake system.

The truck has a Tow/Haul and Exhaust Brake (I'm always looking for recommendations from other members with a similar hitch setup).

I'm also looking for other 'gotchas' that I may not have considered.

Incidentally, will Tune need an update with the new gearing?

TIA