When adding the oil to the crankcase or changing the oil or filter, it is important that oil of an equal quality to original be used in your car. The use of inferior oils may void your warranty. Generally speaking, oil that has been rated "SF (from 1981) or SE (prior to 1981), heavy-duty detergent" by the American Petroleum Institute will prove satisfactory.
Oil of the SF (from 1981) or SE (prior to 1981) variety performs a multitude of functions in addition to its basic job of reducing friction of the engine's moving parts. Through a balanced formula of polymeric dispersants and metallic detergents, the oil prevents high temperature and low temperature deposits and also keeps sludge and dirt particles in suspension. Acids, particularly sulphuric acid, as well as other products of combustion of sulphur fuels, are neutralized by the oil. These acids, if permitted to concentrate, may cause corrosion and rapid wear of the internal parts of the engine.
It is important to choose an oil of the proper viscosity for climatic and operational conditions. Viscosity is an index of the oil's thickness at different temperatures. A thicker oil (higher numerical rating) is needed for high temperature operation, whereas thinner oil (lower numerical rating) is required for cold weather operation. Due to the need for an oil that embodies both these characteristics in parts of the country where there is wide temperature variation within a small period of time, multigrade oils have been developed. Basically a multigrade oil is thinner at low temperatures and thicker at high temperatures. For example, a 10W-40 oil exhibits the characteristics of a 10 weight oil when the car 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, let's say, a straight 30 weight oil. But after the engine reaches operating temperature, the 10W-40 oil begins acting like a straight 40 weight oil, its heavier weight providing greater lubricating protection and less susceptibility to foaming than a straight 30 weight oil. Whatever your driving needs, the oil viscosity-temperature chart should prove useful in selecting the proper grade. The SAE viscosity rating is printed or stamped on every oil container.
It is important that you use fuel of the proper octane rating in your car. Octane rating is based on the quantity of anti-knock compounds added to the fuel and it determines the speed at which the gas will burn. The lower the octane rating, the faster it burns. The higher the octane, the slower the fuel will burn and a greater percentage of compounds in the fuel prevent spark ping (knock), detonation and preignition (dieseling). Your car is equipped with a catalytic converter making the use of unleaded fuel mandatory.
OIL LEVEL CHECK
Check the engine oil level every time you fill the gas tank. The oil level should be above the ADD mark and not above the FULL mark on the dipstick. Make sure that the dipstick is inserted into the crankcase as far as possible and that the vehicle is resting on level ground.
Don't check the level immediately after stopping the engine; wait a few minutes to let the oil drain back into the pan.
OIL & FILTER CHANGE
The engine oil and oil filter should be changed at the recommended intervals on the maintenance schedule chart. After the engine has reached operating temperature, shut it OFF, firmly apply the parking brake, block the wheels, place a drip pan beneath the oil pan and remove the drain plug. Allow the engine to drain thoroughly before replacing the drain plug.
On some V8 engines a dual sump oil pan was used. When changing the oil both drain plugs (front and side) must be removed. Failure to remove both plugs can lead to an incorrect oil level reading.
Place the drip pan beneath the oil filter. To remove the filter, turn it counterclockwise using a strap wrench. Wipe the contact surface of the new filter clean of all dirt and coat the rubber gasket with clean engine oil. Clean the mating surface of the adapter on the block. To install, hand turn the new filter clockwise until the gasket just contacts the cylinder block. Do not use a strap wrench to install. Then hand turn the filter 1 / 2 additional turn. Unscrew the filler cap on the valve cover and fill the crankcase to the proper level on the dipstick with the recommended grade of oil. Install the cap, start the engine and operate at fast idle. Check the oil filter contact area and the drain plug for leaks.
Certain operating conditions may warrant more frequent oil changes. If the vehicle is used for short trips, where the engine does not have a chance to fully warm-up before it is shut OFF, water condensation and low temperature deposits may make it necessary to change the oil sooner. If the vehicle is used mostly in stop-and-go traffic, corrosive acids and high temperature deposits may necessitate shorter oil changing intervals. The shorter intervals also apply to industrial or rural areas where high concentrations of dust and other airborne particulate matter contaminate the oil. Finally, if the car is used for towing trailers, a severe load is placed on the engine causing the oil to "thin-out" sooner, making the shorter oil changing intervals necessary.