Slowing down to the speed limit can make a huge difference especially if you drive a vehicle with poor aerodynamics (SUV). Every 5 mph over 65 mph will decrease your fuel efficiency by 7% on average. I used to drive 70-75 mph (when possible) and now that I’ve slowed down to 65 mph I’ve seen the fuel economy of my CR-V increase from 23.5 mpg to 26 mpg.
Another change that can greatly increase your fuel economy is to drive more smoothly, giving yourself space in traffic so you don’t have to brake and accelerate as much. This saves me a lot of gas driving to work on the 805, though it doesn’t seem like many subscribe to this theory. Most speed up to the car in front of them, tailgate, slam on the brakes, change lanes and repeat… then when I exit I see the same cars turning right on Mira Mesa Blvd so it doesn’t really get you far.
