See Figure 1
Unleaded gasoline having a minimum octane rating of 87 (R+M)/2 should be used. Engines may respond differently to gasolines having the same octane rating. Should the engine in your vehicle develop spark knock (ping), trying purchasing your gasoline from a different source or try a different brand. Use gasolines containing a high level of detergent additives. The use of a detergent type gasoline will reduce fuel injector and intake system deposit build-up and help maintain an excellent degree of vehicle driveability.
The recommended oil viscosities for sustained temperatures ranging from below 0°F (18°C) to above 32°F (0°C) are listed in this section. Multi-viscosity oils are recommended because of their wider range of acceptable temperatures and driving conditions. When adding oil to the crankcase or changing the oil or filter, it is important that oil of an equal quality to original equipment be used in your vehicle. The use of inferior oils may void the warranty, damage your engine, or both.
The Society of Automotive Engineers (SAE) grade of oil indicates the viscosity of the oil (its ability to lubricate at a given temperature). The lower the SAE number, the lighter the oil; the lower the viscosity, the easier it is to crank the engine in cold weather but the less the oil will lubricate and protect the engine in high temperatures. This number is marked on every oil container.
Oil viscosities should be chosen from those oils recommended for the lowest anticipated temperatures during the oil change interval. Due to the need for an oil that embodies both good lubrication at high temperatures and easy cranking in cold weather, multigrade oils have been developed. Basically, a multigrade oil is thinner at low temperatures and thicker at high temperatures. For example, a 10W-30 oil (the W stands for winter) exhibits the characteristics of a 10 weight (SAE 10) oil when the vehicle is first started and the oil is cold. Its lighter weight allows it to travel to the lubricating surfaces quicker and offer less resistance to starter motor cranking than, say, a straight 30 weight (SAE 30) oil. But after the engine reaches operating temperature, the 10W-30 oil begins acting like straight 30 weight (SAE 30) oil, its heavier weight providing greater lubrication with less chance of foaming than a straight 30 weight oil.
The American Petroleum Institute (API) designations, also found on the oil container, indicates the classification of engine oil used under certain given operating conditions. Only oils designated as SH or better should be used in your vehicle. Oils of the SH type perform may functions inside the engine besides their basic lubrication. Through a balanced system of metallic detergents and polymeric dispersants, the oil prevents high and low temperature deposits and also keeps sludge and dirt particles in suspension. Acids, particularly sulphuric acid, as well as other by-products of engine combustion are neutralized by the oil. If these acids are allowed to concentrate, they can cause corrosion and rapid wear of the internal engine parts.
Oils currently available marked Energy Conserving, Fuel Saving, Fuel Efficient, Gas Saving, etc. on the lower part of the container logo, that meet the viscosity grade requirements are recommended.