truck canopy improve MPG?

[mic1hael]

I am going to put a canopy on my truck and I am just wondering if that will help get better MPG? I would think it would considering the wind doesn't have to slam into as much of the TT than without. Anyone out there have ideas either way?

[Hansel]

I have a fiberglass lid for my truck, but I see no improvement in fuel mileage with it on the truck which they advertise will increase your fuel mileage. And as far as the towing for me no difference with the lid on or off, I know your talking about a shell that would run the same level as the truck cab so I would think the same thing that your TT would tow easier because of less wind hitting the nose of the camper.

[Halibutman214]

I have one and the answer is no. If it does it's so insignificant it doesn't matter.

[Bob Landry]

Insignificant change. it does let you carry things in the bed protected from the elements and that's what I use it for.

[JRTJH]

Some of the older wedge shaped toppers may have improved aerodynamics, but the one I had did little for fuel mileage. Maybe it was the extra weight of the topper negated the fuel advantage? Who knows, but if you're going to put a topper on the truck, do it for convenience and for looks, not for fuel mileage improvement and you'll be satisfied.

[hankaye]

Howdy All;

Mythbusters did a project on this back in 06,07 or somewhere in that time frame...
Did the check with tailgate up,down with a cap and without, with a flat cover .....
best mileage they got was with tailgat in up position.
What they found was the air comes over the cab and hits the tailgate,
which in turn pushes the air forward to the back of the cab (ever open the sliding
window with a bunch of leaves in the back???), the air rises then rolls to the back
creating sort of a 'pillow' the new air goes over the cab across the 'pillow' then
back behind the truck........:bdance:

hankaye

[mikell]

EX GM fuel systems engineer here and your truck will get the best with the tailgate up or with a bed level cover. Thats what they are designed for. vehicles are designed to get the best mileage as they roll off the line. Thats the way the government test them

[hankpage]

A cap or cab mounted wing will at best just move the bug-line up a little higher on the trailer but will not improve mpg. The extra dry storage is nice though. Hank

[LittleJoe]

The lip extension on the top of a closed tailgate on the new dodge 1500 is reported to give a .5mpg improvement in windtunnel testing.

A cap on truck pulling a TT may give a very slight benefit? A cap on a stand alone truck does not improve mileage. The most efficient, least amount of drag shape is a teardrop, rounded part forward.

Stopping air from getting under truck and trailer will show far more improvement.

The side skirts you see on tractor trailer rigs (trailers) give a documented 5% increase in fuel economy , as do the singles instead of duals on tractors/trailers. Higher cost of these tires about negates gains though.