1998 Ford F150 Owner Guide 1st Printing - Page 188

Maintenance and care It should not be necessary to add any aftermarket products to your fuel tank if you continue to use a high-quality fuel. Cleaner air Ford approves the use of gasolines to improve air quality, including reformulated gasolines that contain oxygenates up to 10% ethanol or 15% MTBE. Do not use gasolines containing methanol, which can damage critical fuel system components. Damage resulting from the use of methanol may not be covered by your warranty. Calculating fuel economy To accurately calculate your vehicle's fuel economy: 1. Fill the tank completely and record the initial odometer reading. 2. Each time you fill the tank, record the amount of fuel added (in liters or gallons). 3. After at least three to five fuel tank fill-ups, fill the fuel tank and record the current mileage reading. 4. Use one of the following equations to calculate fuel economy. Liters used x 100 Ϭ Total kilometers traveled Total miles traveled Ϭ Total gallons used 188