my suburban sits home while I pull it with my 2500HD. Most everyone knows a stiffer suspension helps with towing, but the wheelbase also makes a huge difference with stability, like when the wind blows.
A crew cab SHORT BED truck is 6+" longer than my suburban. The suburban is quite longer than a Tahoe. Each decrease in wheelbase lessons stability. Then you have tires. E-rated stiff tires will hold the lateral loading better than light-duty tires. This is partially an advantage the duallys have over singles (noted mostly when you drive with slide in campers and the wind blows).
My 5k trailer (when loaded) can be hitched up to my 2500HD without sway control or weight distribution. I'd probably need weight distribution and sway control for my suburban, despite the suburban's ratings being much higher than my trailer.
My discovery 2 could even theoretically pull my trailer, but with a 100" wheelbase it'd be absolutely fatiguing trying to keep that thing straight on the freeway!
In short: A Suburban would be a much nicer towing experience than a Tahoe, even though the weight ratings, engine, tires, and suspension are exactly the same....it just has a significant wheelbase advantage (which also gives you more cargo capacity). I can't stress enough how much a better vehicle the suburban is vs. the Tahoe. The Tahoe looks better, I'll give it that (which is why I bought it first!).