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4.10 Or 3.73 With 8.1 Liter


Charter Member
Full Member
Mar 22, 2002
Sacramento Valley
I saw the post about gears for the 5.3 liter. What about the 8.1 liter?

I have an 8000 lb travel tailor. Will the big motor stay in overdrive at 65mph with 4.10's or would I be better off with 3.73's in drive? Anybody with a similar trailor?
Given the weight of your trailer I would guess that the 2500 [8.1L] with tow/haul engaged would do just fine with the 4.10 gear set. My $.02 ;D
Per the specs, either rear end will do. ?The lower one will give you a little more power. ?You probably won't notice any difference with MPG. ?:)
Also, check out the thread "Av vs GVWR vs trailer towing " in this section.
I have a 2500 Av with the 4.10 rear end. This is just about the top of the line for a towing rig.

Yes, it will stay in overdrive at 65 mph - even towing my 10,000 trailer.

This baby hits hills and doesn't even slow down. Gotta be the magic of the oversized Big block Chev engine and the 4.10s.

Empty, the rig gets 15 on the highway and 11 around town. With the trailer, the mileage is about 11 on the open road. Hey, it's big and it's powerful - I'll gladly buy the gas.