Newbie and can't figure out the "What can I tow" math

Thank you all for chiming in. I came up with the 8400 #’s by entering my VIN on rv.campingworld.com search by VIN to see what I could pull.

With regards to the HD Tow package, I do have the Z82 code on the glove box sticker which I believe to be the code for that package. Additionally, when I go into “tow mode” my battery display on my dash is replaced by what appears to be a tranny temp display.

I have confirmed that I do have the 3.42 rear axel.

The payload on my door jam reads 1,588 lbs