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Wyo George · 12-02-2018, 05:14 PM

I'd say 6-8 mpg is optimistic. We had a bus with a 366 and it averaged 5-6 mpg. It'll be geared to pull so it'll move your trailer, but it won't move quickly. If you're in a rig with over 20k lbs combined with an old gas engine you shouldn't be in that much of a hurry anyway

The Cummins will pull better and use a lot less fuel to do so. It's still not going to be a hotrod, but if you're going to be slow you might as well do it while burning less fuel. Depending on the generation of the cummins it'll either be a little better or a lot better, but either way it'd be my choice if I were buying a truck that size.

12-02-2018, 05:14 PM	#2
Wyo George Registered User Join Date: Jan 2018 Location: Rolling Hills, WY Posts: 21	Re: 366 expectations I'd say 6-8 mpg is optimistic. We had a bus with a 366 and it averaged 5-6 mpg. It'll be geared to pull so it'll move your trailer, but it won't move quickly. If you're in a rig with over 20k lbs combined with an old gas engine you shouldn't be in that much of a hurry anyway The Cummins will pull better and use a lot less fuel to do so. It's still not going to be a hotrod, but if you're going to be slow you might as well do it while burning less fuel. Depending on the generation of the cummins it'll either be a little better or a lot better, but either way it'd be my choice if I were buying a truck that size.