I'm Ok on Tongue Weight.. But my GVW is a little over at the trailer is pretty heavy... I am a a freak about fluid/filter/ maint stuff.....
but on the other hand, if there's not a chance this rear end will last, I;m prob better off either finding a 9.5 now and sell my 8.6
OR if doing a few little things I can make my 8.6 last - of course that's easier and cheaper now.
My camper is a 33' triple slide bumper pull.. It's supposed to be "Half Ton Rated" but I know that's BS. But I did buy this XL Denali
to use as the tow vehicle for it
My 94 Chevy 1500 Ext Cab just got too pushed around and was a lot of white knuckle so we didn't travel as much.
Of course it's highly modded with 421 Supercharged Engine, Built 4L80E w billet converter, 9" Rear End, and lots of suspension and
brake upgrades. Freaked people out when my tow vehicle runs 11.50s at the track !!!
This Denali is on its way to "Being Mine". And I'll have a ton more interior space for Dogs/Stuff/Grandkids
You didn't say how much the trailer weighs. But being that big, with triple slides, I'm guessing 7-8k easy. Which is, IMHO, too much for your Denali. I've had four trailers and two tow vehicles.
My experiences:
1) 1500 pulling a 28-footer, 4550 dry, just under 6k loaded - good combo, kids were small, towed from Michigan to Florida multiple times with no issues
2) 1500 pulling a 6500-lb, 28 footer - borrowed a friend's trailer a few times, noticeably heavier, had crappy brakes and was frequently downshifting to save the Suburban's brakes (another issue for your truck - GM half-tons are underbraked). Spun the pinion bearing on the rear diff on a trip to Washington, DC/Virginia. Wife and kids went on without me, I got to spend 4 days of my vacation in lovely Youngstown, OH.
3) 1500 pulling a 28-foot, 7,000-lb triiple bunk with 36" slideout - Overheated the rear axle, cooked out all the fluid, and grenaded the rear on a long drive from Minnesota to Wyoming. Got to spend four days in lovely Mitchell, SD (the corn palace!!!) while a new rear was trucked in from Minneapolis. Wife and kids were not happy we were in Mitchell instead of Rushmore and Yellowstone.
You're supposed to break in a new rear and drive lightly for 500 miles. After losing 4 days on our vacation, I wasn't about to spend another day driving in circles for 8 hours. Improper breakin led to a non-towing failure a year later. Which leads us to what I have now....
4) 2500 pulling a 35-foot double slide, 8600 lbs loaded. With the family on board, me, wife, three grown kids, we're maxing out the Suburban. Rear axle right at 5500, GVW right at 8600, GCW right at 16,000.
The 10.5" free-floater is the stuff of legends. Rated to 8600 lbs by American Axle, it's probably the stoutest component on the whole truck. The tires are the limiting factor on weight, not the axle. The only thing more badass is the 11.5" rear found on the HD trucks.
Lastly, my 2500 has towed heavy about 20,000 miles, the odometer is at 197k, and it's still ALL original.