I tow my Jayco hybrid with a 2012 Chevy Silverado with the 4.8 V8 and 3.23 gears. It does just fine in Florida where it's flat. The owners manual says I can gain 2000 lbs. towing capacity changing to ...
And "just dropping a gear in the trans" is not the same as changing the gear ratio! When you change the ring and pinion each gear in the trans is much more efficient at moving a load!