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 car. The use of inferior oils may void the warranty, damage your engine, or both.
The SAE (Society of Automotive Engineers) grade number 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 viscosity's 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-40 oil (the W stands for winter) exhibits the characteristics of a 10 weight (SAE 10) 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, say, a straight 30 weight (SAE 30) oil. But after the engine reaches operating temperature, the 10W-40 oil begins acting like straight 40 weight (SAE 40) oil, its heavier weight providing greater lubrication with less chance of foaming than a straight 30 weight oil.
The API (American Petroleum Institute) designations, also found on the oil container, indicates the classification of engine oil used under certain given operating conditions. Only oils designated for use Service SJ, or latest superceding designation, heavy duty detergent should be used in your car. Oils of the SJ 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 sulfuric 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.
Oil & Filter Change
The oil and filter should be changed every 7,500 miles (12,000 km) under normal service and every 3,000 miles (5,000 km) under severe service.
The oil should be changed more frequently if the vehicle is being operated in a very dusty area. Before draining the oil, make sure that the engine is at operating temperature. Hot oil will hold more impurities in suspension and will flow better, allowing the removal of more oil and dirt.
It is a good idea to warm the engine oil first so it will flow better. This can be accomplished by 15-20 miles of highway driving. Fluid which is warmed to normal operating temperature will flow faster, drain more completely and remove more contaminants from the engine.
- Raise and support the vehicle safely on jackstands. Make sure the oil drain plug is at the lowest point on the oil pan. If not, you may have to raise the vehicle slightly higher on one jackstand (side) than the other.
- Before you crawl under the vehicle, take a look at where you will be working and gather all the necessary tools, such as a few wrenches or a ratchet and strip of sockets, the drain pan, some clean rags and, if the oil filter is more accessible from underneath the vehicle, you will also want to grab a bottle of oil, the new filter and a filter wrench at this time.
- Position the drain pan beneath the oil pan drain plug. Keep in mind that the fast flowing oil, which will spill out as you pull the plug from the pan, will flow with enough force that it could miss the pan. Position the drain pan accordingly and be ready to move the pan more directly beneath the plug as the oil flow lessens to a trickle.
- Loosen the drain plug with a wrench (or socket and driver), then carefully unscrew the plug with your fingers. Use a rag to shield your fingers from the heat. Push in on the plug as you unscrew it so you can feel when all of the screw threads are out of the hole (and so you will keep the oil from seeping past the threads until you are ready to remove the plug). You can then remove the plug quickly to avoid having hot oil run down your arm. This will also help assure that have the plug in your hand, not in the bottom of a pan of hot oil.
- Allow the oil to drain until nothing but a few drops come out of the drain hole. Check the drain plug to make sure the threads and sealing surface are not damaged. Carefully thread the plug into position and tighten it snug, and give a slight additional turn. You don't want the plug to fall out (as you would quickly become stranded), but the pan threads are EASILY stripped from overtightening (and this can be time consuming and/or costly to fix).
- To remove the filter, you may need an oil filter wrench since the filter may have been fitted too tightly and/or the heat from the engine may have made it even tighter. A filter wrench can be obtained at any auto parts store and is well-worth the investment. Loosen the filter with the filter wrench. With a rag wrapped around the filter, unscrew the filter from the boss on the side of the engine. Be careful of hot oil that will run down the side of the filter. Make sure that your drain pan is under the filter before you start to remove it from the engine; should some of the hot oil happen to get on you, there will be a place to dump the filter in a hurry and the filter will usually spill a good bit of dirty oil as it is removed.
- Wipe the base of the mounting boss with a clean, dry cloth. When you install the new filter, smear a small amount of fresh oil on the gasket with your finger, just enough to coat the entire contact surface. When you tighten the filter, rotate it about a quarter-turn after it contacts the mounting boss (or follow any instructions which are provided on the filter or parts box).
- Remove the jackstands and carefully lower the vehicle, then IMMEDIATELY refill the engine crankcase with the proper amount of oil. DO NOT WAIT TO DO THIS because if you forget and someone tries to start the vehicle, severe engine damage will occur.
- Refill the engine crankcase slowly, checking the level often. You may notice that it usually takes less than the amount of oil listed in the capacity chart to refill the crankcase. But, that is only until the engine is run and the oil filter is filled with oil. To make sure the proper level is obtained, run the engine to normal operating temperature, shut the engine OFF , allow the oil to drain back into the oil pan, and recheck the level. Top off the oil at this time to the fill mark.
- Drain your used oil in a suitable container for recycling.
Oil Level Check
The engine oil dipstick is typically located in the front of the engine near the exhaust manifold.
Engine oil level should be checked every time you put fuel in the vehicle or are under the hood performing other maintenance.
- Park the vehicle on a level surface.
- The engine may be either hot or cold when checking oil level. However, if it is hot, wait a few minutes after the engine has been turned OFF to allow the oil to drain back into the crankcase. If the engine is cold, do not start it before checking the oil level.
- Open the hood and locate the engine oil dipstick. Pull the dipstick from its tube, wipe it clean, and reinsert it. Make sure the dipstick is fully inserted.
- Pull the dipstick from its tube again. Holding it horizontally, read the oil level. The oil should be between the MIN and MAX marks or the notches on the dipstick. If the oil is below the MIN mark or lower notch, add oil of the proper viscosity through the capped opening of the valve cover.
- Replace the dipstick, and check the level again after adding any oil. Be careful not to overfill the crankcase. Approximately one quart of oil will raise the level from the low mark to the high mark. Excess oil will generally be consumed at an accelerated rate even if no damage to the engine seals occurs.
There are many excellent synthetic and fuel-efficient oils currently available that can provide better gas mileage, longer service life and, in some cases, better engine protection. These benefits do not come without a few hitches, however; the main one being the price of synthetic oil, which is significantly more expensive than conventional oil.
Synthetic oil is not for every car and every type of driving, so you should consider your engine's condition and your type of driving. Also, check your car's warranty conditions regarding the use of synthetic oils.