The trans and other parts of the drive-train is part of the issue. If I regear, it will lessen the stress on the rest of the driveline. Rears are stupid and purely mechanical. They aren't going to fail unless you're doing something stupid or not maintaining it. The engine and trans on the other hand are going to be working much harder with the extra width/diameter/weight of the tires plus the 5000lbs of load.
Being new to diesels, and specifically the 7.3, does anyone know the best RPM for it? I thinking that may make the decision easier. With the stock gears and new tires, the RPMs will be around 1830 at 70. That seems awefully low, with 5000 extra pounds. I would think it be better to have the RPMs closer to 2200, which is where it'd be with the 4.30s in OD.
I appreciate the input you guys are giving. For eye candy, here is a picture of the new wheels/tires. The ones in the background are from my old truck, a lifted '96 Bronco. Hated to give that up, but really wanted something that could tow better.
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Don
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