Oil is the lifeblood of your vehicle, so keeping it clean, fresh and topped off is crucial to the well-being of your automobile. Oil helps lubricate the moving parts of your car and will keep it running cooler and smoothly.
So when should you change it, and with what?
Your best friend and adviser as to when to change your oil and what weight and type to use is your auto manufacturer; check your owners manual for recommended service times and viscosity (weight) of the oil. The manufacturer may also recommend whether you should use a synthetic oil or you should use a mineral oil. If you hear a ticking sound while you are stopped, that is generally a sign that you are low on oil, and it should be checked immediately.
Manufacturer recommendations usually fall somewhere in between three months/3,000 miles and 24 months/20,000 miles. Newer cars are built for maximum performance. Keep in mind that most manufacturers assume that your car's use is light-duty, so be sure to make adjustments for heavy-duty use if you use your vehicle for towing, for a lot of stop-and-go driving, for climbing mountains or in severe weather conditions. It's a good idea to routinely check the oil level in between changes (using the dipstick), topping the oil off if it's low.
Viscosity is the fluid's resistance to flow and is manufacturer-measured at zero degrees Fahrenheit. Hot weather thins motor oil, whereas cold weather thickens it. The less resistant an oil is to thinning the greater the difference between the two numbers will be on an oil's label. For example, 10W-30 has less viscosity than 20W-50. Though thicker oil is better for lubrication, if it is too thick it can be harder to start the engine and will reduce fuel economy. The American Petroleum Institute grades oils using SM for gasoline engines and CJ-4 for diesels, but be sure to use the viscosity recommended by your car's manufacturer. Check the label on the oil container to determine the mix and quality.
There are three main motor oil types on the market. Group 4 oil, branded as synthetic, is made from simpler compounds and fine-tuned to adjust viscosity, allowing for more flexibility in high and low temperatures. Group 3 lubricant is a synthetic blend made from reprocessed petroleum products. Mineral motor oil is the least expensive and made from a mix of crude oils. All of the oils will do the job well as long as you are using oil that has the correct viscosity. Many owners of new and high-performance cars prefer to use synthetic oil in their engines. There is concern that changing to synthetic oil after using mineral oil for a long time could cause sludge from engine deposits to break off.
No matter whether you choose mineral oil or a synthetic oil, automotive expert Lauren Fix, "The Car Coach," says, "it's critical to routinely check the engine oil and transmission fluid to ensure they're at the proper level." Notice the color of the oil. It starts honey-colored and gets darker as it gets older; sludge looks like a gelatinous goop.
For do-it-yourselfers: Have necessary new oil and a new oil filter on hand. Change your oil on level ground. Let the vehicle idle for about 10 minutes to warm the engine. Apply the parking brake and use wheel chocks before jacking up the vehicle. Use jack stands, as well. Place a drain pan under the engine, and remove the oil cap. Remove the oil plug. (Check the manual schematic for location.) Let the oil drain out completely. Replace the plug with a new washer. Locate and unscrew the oil filter. (Check schematic for location.) Let the old filter sit in a plastic bag. Pour a small amount of oil into the new filter, and wipe the opening with the oil. Screw the new filter in place as tightly as the manufacturer's directions say. Add new oil at the oil fill hole; check the manual for how much oil you need. Replace the fill cap, and remove the drain pan. Remove the jack stands, and lower the car. Wipe up any drips you see before starting the engine.