[FLexpat]

• My 89 full size Blazer (350/4WD) was really good at towing my 20' Bertram which weighed about the same as the 23. My recollection is that mileage was marginal.
• Step-daughter's '05 Cadillac Escalade (4D 'pickup wannabe' with a 6.0L and AWD) even though it has a 7300lb tow capacity is ok for towing smaller loads but poor for anything over ~4000 lbs; it really struggles with a small (2) horse trailer and handling while towing is squirrely with the short wheelbase and soft air suspension. 15mpg not towing, 11mpg towing
• My '14 2500 Silverado diesel (3/4 ton) w crew cab and 6.5' bed doesn't care if anything is behind it and tows (and stops) a 10,000lb horse trailer at 7000' altitude and up mountains or at stupid fast speeds just fine. I did put on slotted rotors to keep from warping them on steep grades. Significant overkill for a boat though. Depending on speed; 18-22mpg not towing, 10-14mpg towing (really drops over 80 though).