According to the v8 swap guy with every ASE certification and like 3 ECUs.... It's the exact thing as a Colorado. Check your privilege hahahahaHave you read the Hummer H3 Launch book HERE? In it, a GM person (I forget..proj mgr??) indicated the H3 ended up containing about 15% parts from the Colorado. The rest unique. It's a good read if you haven't read it. Kind of a Must-Read for a H3 enthusiest. Your library might have it.
But yeah, it's can be somewhat frustrating. Now's the time to re-do the tranny while parts ARE available. I wouldn't be afraid to tow small trailers. Probably not a car trailer up over the mountains (in your case) ..though
I miss that thread.