Your trans is virtually identical to mine on my 08. Tow haul is NOT like the old version where it took out gears and left your engine spinning like mad.
It changes your shift points from about 1200rpm's to closer to 1500. This keeps the engine in the max torque range and lets the engine work.
It will downshift much more aggressively. In normal the trans will disengage and let the engine freewheel. In TH it stays locked up to allow the engine break to work harder to keep you off of your wheel brakes
It does not remove any gears. All 6 are available. I try not to use 6th unless going close to 65 because I live in mountain country and am always shifting down anyway. Picked up about 1 MPG holding 6th out and going 60ish.
TH works great on the newer rams with the 6 speed trans
Chris