Cruise control or not?

August 24, 2010

Will cruise control improve fuel economy?

The answer: it depends.

On level highways with light traffic, it is YES: cruise control holds a vehicle to a steadier speed than most drivers can, and that’s more efficient than continuous acceleration and deceleration.

However, in hilly terrain, cruise control ‘tramps on it’ when it encounters a climb, trying to maintain a constant speed – and that consumes a lot of fuel.  So in hilly areas, a driver with a skilled foot can easily get better mileage than cruise control.  (A skilled foot means allowing the vehicle to slow down on the upgrades instead of tramping on the gas, and then using the other side of the hill to pick up speed.)

One caveat: safety first!  Always ensure your driving style is compatible with road and traffic conditions.

Thanks to Stephanie McClellan in St. Anthony, NL for the question that led to this Green Idea!

Standard or automatic?

August 9, 2010

Does the type of transmission in your vehicle affect your mileage?

It does!  Generally speaking, vehicles with automatic transmissions use more fuel than similar vehicles with manual transmissions.  A comparison of the 2010 models listed below produced the following results:

On average, manual transmissions will result in fuel savings of about $60 per year.

In city driving, manual transmissions will go about 7% further on a litre of fuel, or about 32 KM further per tank.

In highway driving, manual transmissions will go about 1.3% further on a litre of fuel, or about 8 KM further per tank.

Note that savings vary for every model of car, so it’s wise to check NRCan’s Fuel Consumption Ratings here before buying.  Also, some models now have continuously variable transmissions, which are often even more efficient than manual.

2010 models compared: Chevrolet Aveo and Cobalt; Ford Fusion; Pontiac G3, G5 and Vibe; Honda Civic; Nissan Frontier and Versa; Toyota Corolla, Matrix and Yaris