Along with good up-keep, new tires and checking the tire pressure monthly will help with the bumps along the road. After all, girls love new shoes. You don't want to leave the tires unchecked, because in the event of a flat or leak, you want to make sure you can patch up whatever life throws your way and strengthen the bond you already have. We all have a hard time remembering to check the tire pressure every month, but it's important. Even the spare needs to be checked, just in case it needs to be used in the event of a flat tire. Driving on a flat -- or almost flat -- tire will affect the ride, handling, traction, and safety, so mark one day each month on your calendar to do this.