Adding Equipment to the Outside ofYour VehicleThings you might add to the outside of your vehicle canaffect the airflow around it. This may cause windnoise and affect windshield washer performance. Checkwith your dealer before adding equipment to theoutside of your vehicle.FuelThe 8th digit of your vehicle identification number (VIN)shows the code letter or number that identifies yourengine. You will find the VIN at the top left of theinstrument panel. See Vehicle IdentificationNumber (VIN) on page 5-103.Gasoline OctaneIf your vehicle has the 3.6L V6 engine (VIN Code 7),use regular unleaded gasoline with a posted octanerating of 87 or higher. For best performance or trailertowing, you may choose to use middle grade 89 octaneunleaded gasoline. If the octane rating is less than87, you may notice an audible knocking noise when youdrive, commonly referred to as spark knock. If thisoccurs, use a gasoline rated at 87 octane or higher assoon as possible. If you are using gasoline rated at87 octane or higher and you hear heavy knocking, yourengine needs service.If your vehicle has the 4.6L V8 engine (VIN Code A),use premium unleaded gasoline with a posted octanerating of 91 or higher. You may also use regularunleaded gasoline rated at 87 octane or higher, butyour vehicle’s acceleration may be slightly reduced, andyou may notice a slight audible knocking noise,commonly referred to as spark knock. If the octane isless than 87, you may notice a heavy knockingnoise when you drive. If this occurs, use a gasolinerated at 87 octane or higher as soon as possible.Otherwise, you might damage your engine. If you areusing gasoline rated at 87 octane or higher and you hearheavy knocking, your engine needs service.5-5
