[sourdough]

James, first welcome to the forum! Lots of good folks and tons of knowledge here. Secondly, I applaud your effort at trying to use that spreadsheet to see if your truck was OK for that trailer. Unfortunately as has been mentioned, it's really not.

The spreadsheet is obviously inaccurate which led you to an inaccurate decision. Even by the spreadsheet, with a combo that had an 84lb. margin before being overloaded.....why go there?

Look at the numbers provided by others previously which will be more accurate and real life. The weight of the 4 point hitch (I'm assuming Equalizer) will exceed 100lbs. 200lbs. for everything else in the truck might get you by if you don't do anything everywhere you go, don't air up the tires, no toys, bbqs etc. Figure more like 500 I would think - what about a compressor when you need it for ???

All of those things from folks trying to make you cognizant of the fact you are going to be in a not so perfect scenario if not careful. The key is to be honest with yourself and DW. Load that truck and trailer like you mean to use it for a while...REALLY use it with the stuff you need to have (and eventually will) for a fun, no stress trip - then go to a scale. That is the definitive answer for you.