Not waaay to much trailer, but maybe waaay to much for you to tow with a short wheelbase lighter rig like the Envoy.
Drivetrain is same as a half ton or Yukon/Suburban so you're golden there.
Suspension is another story. Will need some help there no question.
I wouldn't prefer to pull a 24-26' trailer behind a midsize, but pretty sure I've done more with less. At least you got the big V8 to stretch the whole thing straight if the trailer starts driving the truck. And if you don't know what I mean by that, prolly not a good idea to tow something that long.