Effects of a canoe on gas mileage (OT i guess)

Travelling east coast to west coast, anyone make a guess on how much a canoe on the roof would effect gas mileage? Thanks

If I remember correctly my truck gets 14mpg with a canoe and 19 without at approx 55mph.

Ballpark 3-6 mpg decrease? It really depends on your vehicle and how fast you drive. If you're plowing through at 70+mph it's going to be pretty significant. Based on my trip last summer, you should notice some improvement if you keep it under 60 or even 65.

I carry a canoe all trout season on a 2004 Tacoma, it doesn't change the mileage at all. It's aero-dynamic like a missile, weighs about 1/2 a human. I do notice cross winds rocking the truck, but no mileage change. I also write my gas and mileage with every fill up.

Depends on the vehicle. If your vehicle has really good aerodynamics and a relatively small, low powered engine (like my '06 Civic), then you're going to take a big hit, 20-30%. The faster you go, the bigger the hit. On a bigger, more powerful vehicle with a lot of frontal area to start with, putting a canoe on top won't change the aerodynamic profile as much or affect the engine load as much, so the hit to the gas mileage won't be as bad. Of course vehicles like that don't get the best mileage to start with...

Putting anything on your roof will cause a noticeable hit on fuel economy. Regardless of what vehicle you are driving, the canoe is going to require a certain amount of power to propel it through the air, and that power will have to come from increased fuel consumption.

I agree that the perceived fuel consumption increase is less noticeable in larger vehicles, but this has less to do with the fact that the vehicle is large and more to do with the fact that MPG is a poor unit of measurement to measure fuel consumption as the scale is not linear.

Take the two below examples:

40 MPG down to 35 MPG

14 MPG down to 13 MPG

Which vehicle took a larger hit? The correct answer is the latter example, despite appearances. 14 down to 13 is a larger quantity of fuel than 40 to 35. That can affect people's opinion of larger vehicles, which might only take a 1-2 MPG drop, thus implying they are less effected by load.

Remember, aerodynamic drag increases as the square of velocity. The higher the speed, the lower the fuel economy, and the more drag your vehicle has to begin with, the larger the effect as you increase speed.

Hmmmmm. Interesting. Thanks all for the input. Anyone have a ball park $ guess for a minivan travelling from the east cost of Canada to West coast? Kinda stupid to ask I know. Im just curious if its worth to have a canoe in BC to paddle some cool lakes and stuff