1997 Ford F350 Owner Guide 1st Printing - Page 295

underhood Vehicle Emissions Control Information label) are designed to operate on California reformulated gasolines. If California reformulated gasoline is not available when you refuel, your vehicle can be operated on non-California fuels. However, even though your engine will perform adequately on other gasolines, the performance of the emission control devices and systems may be adversely affected. Repair of damage caused by using a fuel that your vehicle was not designed for may not be covered by your warranty. Octane recommendation Your vehicle is designed to use regular unleaded gasoline with an (R+M)/2 octane rating of 87. We do not recommend gasolines labeled "regular" in high altitude areas that are sold with octane ratings of 86 or even less. Typical octane rating label Do not be concerned if your vehicle sometimes knocks lightly. However, if it knocks heavily under most driving conditions on the recommended octane rated fuel, see your dealer or a qualified service technician to prevent any engine damage. Fuel quality If you are experiencing starting, rough idle or hesitation problems, try a different brand of fuel. If the condition persists, see your dealer or a qualified service technician. 296