I tow a 6500GVW camper with a 1996 1500 Suburban. 4 people and all our stuff. We have even done 6 people, but that was only down I95 on the east coast. Not as flat as you would expect, but no huge mountains either.
3.73's and tow package. It does the job. I lock out overdrive and set the cruise around 60.
I have the better later model cooling fan and the heaviest duty fan clutch they had, and a catless manderel bent mid pipe. Some brake and suspension mods since it is a 1500, but you are good there with a 2500.
If you have the 5 blade metal fan it would be worthwhile to upgrade yours. Rockauto sells them for around $50 No comparison between the two. You should have the big factory mid pipes already since it is a 2500 so you are good there too.
Expect it to downshift on hills. you will slow down and maybe hit 2nd on really serious grades. But it will do the work, just keep and eye on the engine temp.
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