I tow and DD an 04 Tahoe and it works very well for me. I'm towing a fairly heavy Toyota on a 16' trailer. It has been to Moab, and five mile pass several times with out any issues. Mine has the auto ride (air bags) and that really helps. I also have had a little computer work done to help out with horse power (I'm guessing it is somewhere around 325hp maybe 330hp) and shift points. I only get around 12mpg with the trailer and around 18mpg with out.
I pm'd you, but thought I'd add it here in case others have the same question. Which motor/trans are your running in the Tahoe? How fast can you tow over the Yota over Soldiers Summit? I've been thinking of getting something more mpg friendly than my current truck.
I have an Expedition Limited with air suspension. Best towing SUV next to the diesel Excursion. I ordered it with the lower gears so I could put 22's and 305's on it.
Both rear row seats fold down flat, plenty of head room and leg room in the third row. All of which the GMs don't have.
It has no problem pulling my jeep over Soldier Summit faster than the speed limit or my 24' Chaperell(heavy boat) with 7 or 8 people in it. The air ride levels it right out.
What motor/trans do you have in the Expedition? What MPG do you get in town, on the highway, and towing?