Weigh your current rig at any truck stop.
Compare that to the sticker on your door or SPECs from the internet.
That will tell you exactly how much your crap weights.

Look at drive ratios.
Are you doing mountain driving or are you zipping on flat highway speeds?
do you need 3.31 or 4.1 on your rear diff?
Looks like your options are: Final drive 3.31:1, 3.73:1, 4.10:1

Personally, I do mostly highway driving in my van at around 70-100MPH.
I hardly ever tow anything.
I'm also over a mile high (ASL), so N/A engine is not optimal (turbo or supercharge would be better to compensate for thin air).
YMMV


Most of all, rent it or take it for extended test drive.

I own a 275gal IBC water tote. That thing weighs ~2,400lbs when full.
You can get a used tote for free to $100.
If you don't have a forklift, install it empty (only little over 128LBS) -- strap it down -- fill it with water -- drive around -- drain and remove when done.
Or buy a pallet of bricks/blocks/cement/pellets. Drive it around and then return it. Yes, make sure HD will load it on a pallet.