[RickNewcomb]

I'll just add my experience. I have a 1999 Plymouth Grand Voyager with the factory towing package and a 1999 TM 2619. I use only a WDH. I have over 18,000 tow miles with the TM and over 102,000 miles on the TV. Haven't had the hitch drag once. I do replace the coolant and transmission fluid every two years.