SUVs and Travel Trailers vary greatly. All of the hybrids I've looked at were HEAVY. Weight was going to be an issue, so that caused me to look at other options.
My Xterra is rated at 265 Hp, 284 ft-lbs. Very healthy motor. But it's short wheelbase limits it to 5000 lbs. My previous Nissan had almost 100 less Hp and ft-lbs of torque, yet still had the same tow rating.
This SUV has more power than a previous 5.0L E-150 and a 350 cu in G-10 (both full sized vans).
My TT is rated at 3576 lbs empty. From the factory, with all the options, it weighs 3993 lbs. I travel light, with no more than 10 gallons of fresh water, waste tanks empty. It's a 7 1/2' wide model, so not much wider than the Xterra. Also not much taller. It is 25' long, but since it's in the slip stream of the SUV (mostly), it doesn't matter much that it's a longer trailer.
I'm using an Equalizer hitch, and the trailer behaves itself when towed. The Xterra has plenty of power for the on ramp, passing, or going over bridges (we have no mountains in FL!). The trasmission is an A/T, and I leave it out of OD, so it's running in 4th gear.
About 2600 RPMs at 63 MPH. Worst mileage with heavy headwinds was 8.3 MPG. Best so far was 11.1 MPG.
Very pleased with the setup. But if I was looking at a heavier hybrid, I'd want a V-8.