Don’t carry unnecessary items in your trunk or luggage compartment. Every 45 kg (100 lbs) can cost you 2% more in fuel. If you are carrying tools that you don’t need, golf clubs that you are not using, or in some cases just stuff that you don’t really need, take the junk out of your trunk!
In winter, make sure to not only clear the snow off the top of your car, but clean out the wheel wells too. Snow build up can add significant weight to your vehicle and can affect the handling as well.