I get anywhere from 14-18 in the city and 18-24 on the highway. I have a lead foot too. Not sure but I would think that depending on how you drive a 6 speed would depend on fuel mileage compared to auto trans.
It depends how you want to measure it.
If I include warm-ups and idling it is about 18 for mostly rural driving when not hauling a trailer or other load. My warm-ups are minimal in the driveway ( <30 sec) and I don't have to do much idling in traffic. For cruising on interstates I can get up to 20 if I "CHEAT" by waiting until it is warm and up to cruising speed and then clearing the trip numbers - and by keeping down to 60. This is on a 3600 chassis cab, 4wd, allison automatic with 3.73 axles, dual rear wheels, 215/85 x 16 at 65 psi. It has an alumin platform, weighs 7100 road ready. You could/should be able to get a mile or two better than this, it is VERY right foot weight dependant
I expect it will loosen up some more, it will probably reach peak looseness around 10K. I watch the instantaneous MPG calculation a LOT, it really is more economic at 60/65 on the interstate using cruise control than at 40/45 on rural roads. Getting up to speed is where the fuel gets burned (obvious, but the display really puts it in your face).
I should add that this is in Mass and NH, kinda cold lately, single numbers and slightly negative today.
The 3600 has a 2 piece frame instead of 3,back of cab to wheel a little different length,600 more pounds gvw it is a real chassis cab not just a truck without a box.It is kind of the big daddy of the hd's
.That should get a response
And oh yah it says 3500 on the side you have to look at the frame sticker or in the dash to know.It's a sleeper
If you didn't order it good chance it wasn't ,they are not common.One other thing they have is dual tanks approx. 50 us gallons.Don't think the 3500's can get that?Also my cab to axle is 84.4 inches wheelbase is 161.5 which allows a 11 foot dump body.
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