I recently purchased a 40' fifth wheel toy hauler, triple slide. The dry weight is 14,050 lbs., I figure 1000 lbs. of gear, my motorcycle is about 950 lbs., hers is 650 lbs. We try to two with minimal...
I'm another stick with an Auto. With tow/haul downshifting and engine brakes working together the new trucks are a pleasure to tow with. All three have put a lot of work into their transmissions over the last decade. I wouldn't be as concerned as I once was and BTW I pulled with a 48RE for 10 years. Just take care of what you have and don't tune it but who really "needs" to with the current specs on these trucks.