BNielsen
I'm Awesome
Just my 2 cents on gears - My 5.7 k2500 with 4.10 gears (265 tires) hauls the camper nicely in 3rd gear. It won't stay in OD while pulling, doesn't seem to have enough grunt. I assumed your 7.4 would be enough to make 4.10's the answer, but maybe not? You were stating that you couldn't pull those pallets over 50 mph? I have gone well north of 80 mph (pulling the camper) to pass with my 5.7.
If you are planning/hoping to be able to pull in OD - maybe 4.88 (or lower) is better?
I'm banking on my power issue being a lack of fuel pressure, I'd probably only pull in 4th on flat ground with Tow/Haul on but the rest of the time would be in 3rd depending on load size. I'll just have to see how the truck behaves once I get a massive tune-up and a couple little upgrades done.