[sourdough]

Had one just about yours; same year, axle, engine, cab, tires were the factory 20s, airbags, etc.

I don't know where you got your numbers but I just pulled up 2 sites with specs for that trailer and both show a dry weight of 7590 and payload of 2740 for a gvw of 10,330 (those numbers do seem high to me for that trailer and I think they may be suspect given your scale numbers).

Using your numbers you cut it very close if you are going to have any safety cushion. I like it, some don't care. What I'm seeing says that trailer is about 30' long. If that is correct, and the trailer is weighing about 7200 without being hitched, it seems you should be OK but no safety cushion.

I think the issue with sway is the truck being 1/2 ton and the lighter suspension components. You've added air bags, what do you run them at loaded? What tires do you have? Are they still P rated? If so I would upgrade to LTs. I looked at the wdh/sway you listed. It has the little "add on" sway bar on the side; they never did much for me. If it were me I would put nothing less than the Equalizer 4 point on it. You need effective sway control with a 1/2 ton. I also wonder about how effective the weight distribution is from the hitch - is it cranked up properly. You may need to work on setting it up some more or get a different one. Weight distribution in the trailer could also be a factor. Seems to me like you will have to start tweaking on things because the trailer shouldn't be causing really bad issues.

To your question, the math looks OK. Your thought process appears to be on the right path. The hemi and 3.55 will work with that trailer. You need to keep tow/haul engaged all the time the trailer is hooked up. If it is constantly kicking into overdrive even in tow/haul just lock it out.