Your Experience With Cabover Fuel Mileage

Can’t say anything about cabovers particularly but the guy in the seat has more to do with mileage than anything else.

 

If it’s that one in the picture there you should be able to get pretty much the same mileage as a conventional with the same power. Cab overs don’t really start to pay a big aero price until they’re long enough to let too much air at the front of the trailer. And that’s only really bad with vans. Low deck loads mine were good with. Lumber squared off 3 high on the front trailer was noticeable, but no worse than it would be for a conventional with a flattop.

 

I don't have any personal experience with cabovers but I'd be surprised if it got better than 5 average, which is kind of low for a lower power N14.

 

Really, I never figured the brick wall aero of a cabover would do that well at all.

 

They’re not that bad until they get too long. I used to get the same mileage with my cab overs as my friends single bunk flattop conventionals all got. They were all train tractors though, 244”wb, so anything piled high was right up close to the truck in either case. It’s not like those older conventionals were any better aerodynamically than the cabovers despite the way it looked. It’s not really the difference between the trucks as much as the difference in distance between the cab and the trailer. A 270” cabover won’t get the same mileage as a 270” conventional will. But a cabover at 230” would be really close. Not that much difference if the gap to the trailer is the same.

 

Interesting, I know those N14s will actually do pretty good for mileage in a flattop pulling a flatbed.

 

In the nineties the company I worked for uprated to 500 hp or Down rated to 435 hp if your fuel mileage sucked .. all the 460hp ratings drank fuel according to their records. The other settings did Better and pulled good as well.. cabover economy is tied to your speed more than anything else a buddy has a retrofitted c15 in his shaker he gets low 6’s us mpg pulling a 3 axle weighing about 100,000 lbs but never drives over 62 mph .

 

Not me but my dad got right around 6.2 lifetime avg with a 9700 back when the speed limit was 55 and always coming back empty. Not a flat piece of ground around here. Big cam 4

 

On trains guys I know we’re doing 5.5-5.7 loaded with N14’s, about the same as my Cats. The Cats were a little better empty for some reason. Those were 525’s though. Still a few guys around here running them now on trains and 5axle wagons. You couldn’t give those guys an ISX for free.