How to buy lubricant
A lubricant buying guide
When you want to maintain peak engine performance, it is helpful to know how to buy lubricant for your vehicle or equipment. Engine oil or lubricant uses include lubricating the moving components in an engine and cleaning and cooling the engine, resulting in prolonged life and improved operation. With different types of lubricants available for different types of engines, knowing how to choose lubricant is a matter of understanding the type of engine you have, as well as certifications and viscosity of the lubricant under consideration. Each lubricant has advantages and is suitable for a particular type of equipment or vehicle engine.
>> What are the manufacturer's recommendations?
Check the owner's manual for your equipment or vehicle to learn which types of lubricant the manufacturer recommends. For the best performance, follow the manufacturer's recommendations and avoid using other grades of lubricants. If you are unable to find a recommendation, or don't have an owner's manual, then the next step is to figure out how to buy lubricant on your own. Consider your equipment or vehicle, operating conditions and the age of your engine when choosing a lubricant.
>> What type of equipment or vehicle do you have?
Identifying the type of engine is important when you buy lubricant for your vehicle or equipment. Engines are differentiated by the number of strokes the piston must make to complete a cycle of combustion, as well as the absence or presence of a reservoir for storing engine oil. For example, lawn mowers typically have either a two-stroke or a four-stroke engine. Each uses different types of lubricants, with the two-stroke engine using a mix of gas and oil for fuel and the four-stroke requiring separate gas and fuel.
When you want to know how to choose lubricant for your motorcycle or vehicle, look for a separate reservoir for oil, which means that a separate oil supply is required. To keep the engine operating in prime condition, choose lubricants designed to meet the specifications of your particular engine.
>> Consider certification and designations
Understanding how to buy lubricant is an important part of car care and maintenance, as the right lubricant will go a long way toward maintaining and optimizing engine performance. When you find a lubricant, look for a starburst symbol on the label to identify certification by the American Petroleum Institute (API), which means the oil meets the requirements of the International Lubricant Standardization and Approval Committee (ILSAC). The ILSAC sets certain performance standards in accordance with engine and vehicle manufacturers. Inside the starburst symbol is a recommendation for a particular application, such as "For Gasoline Engines."
Look on the lubricant label for the API donut, which indicates three things:
- The top half of the donut indicates the performance level of the oil.
- The bottom half indicates the engine the lubricant works with, and if the oil has resource-conserving properties.
- In the middle is the SAE viscosity rating.
For example, with the designation "API Service CJ-4," the "C" indicates commercial engines, the "J" indicates the current level of performance and "4" is for a four-stroke engine. All these designations are useful whether you are looking for an exact match to the manufacturer's recommendations or are attempting to choose the best lubricant to buy without formal guidelines.
>> Consider the viscosity of the lubricant
Viscosity, also known as flow rate, indicates how thick a lubricant is at a particular temperature. Viscosity is an important consideration as you learn how to buy lubricant. It is expressed in a numeric value on the container. Look for the SAE letters followed by a number.
Lubricants are available with two types of viscosity: single and multi-viscosity. Single viscosity maintains a consistent thickness regardless of temperature, whereas multi-viscosity changes based on temperature. For example, a multi-viscosity lubricant might be labeled SAE 20W-60. The W stands for winter or low temperature. In this example, 20W indicates flow rate at lower temperatures and 60 indicates viscosity at higher temperatures. The higher the number, the thicker the lubricant.
>> Does your engine require single or multi-viscosity lubricant?
Almost all types of vehicle engines use multi-viscosity lubricants; single viscosity lubricants usually work with equipment and certain operating conditions. Pay attention to the manufacturer's recommendations if you are choosing oil for a new vehicle. If you use oil that is not the recommended viscosity, you might void your warranty.
>> Consider the climate where you operate and the history of the engine
Climate can make a difference in how to choose lubricant. For example, if you experience sharp changes in temperature, multi-viscosity lubricants with a wide range are ideal. In winter, select a lubricant with a lower number before the W. In the heat of the summer, lubricants tend to thin out, and it is often better to opt for higher viscosity.
If you have been using a single viscosity lubricant in an old vehicle, it is not advisable to change to a multi-viscosity lubricant because it may dislodge sludge and cause problems with the engine.
For older engines, you might want to consider switching to a thicker viscosity, as it will provide better coverage and lubrication.
>> What types of lubricant should you use?
When you shop for lubricants in automotive supplies, you will notice that there are three types of lubricants: mineral, synthetic and semi-synthetic, which is a blend of the first two. Mineral lubricants are derived from crude oil by distillation, whereas synthetic lubricants are made from chemicals or crude oil byproducts. There are relatively few performance differences among mineral, synthetic and semi-synthetic.
With synthetic lubricants, there are additional classifications to consider as you choose oil for you engine. This lubricant comparison chart will help you sort out the considerations. Group III and Group IV synthetics are classifications of lubricants that are certified and rated for viscosity. The primary difference between these and any other lubricant is the raw materials used to produce it.
| Group IV ||Chemical compounds engineered to meet certain specifications || |
- Flows freely at very low temperatures
- Does not start decomposing at very high temperatures
- Less friction than mineral lubricants
- Better performance than mineral lubricants
- Improved fuel efficiency
|Group III ||Byproducts left over from making petroleum products || || |
- Same as Group IV
- Better value for many people
Choosing the best lubricant to buy is a matter of understanding the manufacturer's recommendations, the type of engine and other factors such as climate. If you regularly experience temperature swings, a synthetic lubricant might be a good option for your engine. Mineral lubricants tend to be a good option for people who are operating in more stable temperatures.