They have to give you a number, 60 is the number GM chose for that transmission. Towing faster generates more heat, too much heat and the tranny can explode, but that 60 is not hard and fast.
For a mismatch in height usung a towbar, the correction is made with a drop receiver (which can also be flipped to raise the opening at the RV). My hitch is also at 17, two inch drop puts it within safe height for baseplate on the Fit, two inch rise brings it level withthe tabs on my truck.
BlueOx and Roadmaster make the drop receivers, different load limits, different offsets. I've seen 2", 4"' and 8", some at 5000 pounds tow and 150 tongue weight, others up to 8000 tow, 500 tongue weight. They are not cheap, my 2" drop was $80 from E-trailer, dealer wanted almost twice as much.
You want the connection at the MH end of the towbar to be slightly above or level with the connection at the towed vehicle, to prevent it lifting the towbar durung braking. BlueOx frequently gives 3" tolerance, Roadmaster 2", depending on towbar model. But that's not level plus or minus 2-3 inches, it is level to towed vehicle 2-3" lower.
Tom Test
Itasca Spirit 29B
