AMSOIL
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SERVICE LIFE
AMSOIL Signature Series Synthetic Motor Oil is recommended for extended drain intervals in unmodified(1), mechanically sound(2) gasoline-fueled vehicles as follows:

Normal Service(3) – Up to 25,000 miles or one year, whichever comes first.
Severe Service(4) – Up to 15,000 miles or one year, whichever comes first.
In all non-gasoline-fueled vehicle applications, extend the oil change interval according to oil analysis or follow the OEM* drain interval.

*OEM – Original Equipment Manufacturer

(1) Engines operating under modified conditions (non-stock) are excluded from extended drain recommendations. Examples include the use of performance computer chips; non-OEM approved exhaust, fuel or air induction systems; and the use of fuels other than those recommended for normal operation by the manufacturer.

(2) Mechanically sound engines are in good working condition and do not, for example, leak or consume excessive amounts of oil, are not worn out, do not overheat, do not leak antifreeze and have properly working emissions control systems. AMSOIL recommends repairing malfunctioning engines prior to the installation of AMSOIL synthetic oils.

(3) Personal vehicles frequently traveling greater than 10 miles (16 km) at a time and not operating under severe service.

(4) Turbo/supercharged engines, commercial or fleet vehicles, excessive idling, vehicles with more than 100,000 miles without prior continuous use of AMSOIL motor oil, daily short-trip driving less than 10 miles (16 km), frequent towing, plowing, hauling or dusty condition driving.