Better Mileage

[HCuervo]

I know this has been investigated before, but I can't find it again. Do pickup trucks get better mileage with a topper or with the bed open? Or does it make any difference at all?

Thanks,

HCuervo



2004. 4 3500 Lariat, silver, front leveling lift, exhaust brake.

 

[2Gen3Gen]

On the highway, i actually lost 1. 5 mpg at 70 mph with the shell on. Go figure.

 

[Pawpaw]

As I recall, #1 in the mileage category is a tonneau cover. #2 is an open bed with the tailgate up. It all goes downhill from there.



I'm sure my shell is costing me mileage, but it's just too darned handy. Even with it, I can get over 20 MPG on the highway.



Bob

 

[HCuervo]

Mileage with or without a topper.

Thanks for the replies. It makes little sense to think that an open bed would be more fuel efficient. One would guess that the shell would provide more air dynamics for decreasing wind resistnace. The usual topper probably weighs around 200 lbs and for these trucks that is not a sweat breaker. There are plenty of passengers these days that easily exceed that. There are advantages to going topless or with the top on. Within reason. You can ask Dolly Parton.

HCuervo

 

[TSpecht]

The problem with the topper is the drag behind the vehicle it creates, moreso than the empty bed of the truck or the bed with the tonneau cover. Think of it in terms of auto racing, the cars run faster when there's another car behind them, which prevents the air from creating drag behind the lead car and subsequently the other vehicles. The more smoothly the air flowing around the vehicle can come back together the less drag you should be expected to experience.

 

[Badunit]

The only kind of topper that would likely increase mpg would be one that met the roofline at the front and sloped down to the tailgate at the rear. Not very useful but aerodynamic.

 

[bighornram]

http://ask.yahoo.com/20050427.html



Interesting reading... . I would think the shell would have the same resistance from turbulance at the back of the truck as the cab would do without the bubble.

 

[HCuervo]

Thanks, TSpecht!

Your explanation makes sense. The topper creates a suction effect in drag (that is why aircrafts end tapered with a tail). Imagine the drag on the tractor trailers!