I had a 2003 Trailblazer I6 and towed the X20E in my sig.
That Coleman is not as light as you think. It has a 7,600# GVWR. Way too much for that Envoy. Even if you don't pack it to that weight, it'll still be over 5k# when ready to camp. The other issue is payload. The roof on the Envoy XUV is heavy and eats up the already low payload of around 1100# or 1200#. If you have more than 2 people and/or like to carry a lot of stuff you may not have enough available payload. And in the hills of TN? Not going to be fun. I think you'll be looking at 1/2 ton PUs next year.
If you really like the GMT 360/370 platform look for one with a 5.3 v8 and 3:73 gearing.
Chuck D.
โAdventure is just bad planning.โ - Roald Amundsen
2013 Jayco X20E Hybrid
2016 Chevy Silverado Crew Cab Z71 LTZ2
2008 GMC Sierra SLE1 Crew Cab Z71 (traded)