Engine Oil: How Do You Choose The Correct Type For Your Car?

Whether you drive a brand-new hybrid or a classic muscle car, choosing the correct engine oil can be daunting. There is an astonishing amount of oil formulas to choose from these days. Most oil manufacturers market different oil formulas for specific vehicle types, models, and even auto brands. Before choosing an oil for your vehicle, verify it meets your manufacturer’s recommendations. Find this information in your owner’s manual. Once you have selected the correct engine oil, you can perform your auto maintenance or schedule an oil change service with your trusted local auto service center.

Engine Oil Types

Engine oil falls into five distinct types – conventional, high-mileage, synthetic-blend, full-synthetic, and hybrid-vehicle. While each oil type has advantages and disadvantages, it’s important to know their differences to choose the correct one for your auto maintenance needs.

Conventional Oil

Conventional engine oil is refined mineral oil. The formulas come in a range of viscosity grades and quality levels. Auto specialists recommend using conventional oil in older vehicles with simple engine designs.

High-Mileage Oil

High-mileage engine oil formulas work best for late-model vehicles or newer ones with over 75,000 miles. High-mileage oil uses unique chemical additives and formulations to help reduce oil burn-off and prevent leaks common in older engines. 

Synthetic-Blend Oil

Synthetic-blend engine oils are a mixture of full-synthetic and conventional base oils for added resistance to oxidation (compared to conventional oil) while providing excellent low-temperature protection.

Full-Synthetic Oil

Full-synthetic engine oil goes through a chemically engineered process to produce oil molecules uniform in shape with fewer impurities and better properties than conventional oil. In most cases, full-synthetic oil performs better at extremely high and low temperatures. Full-synthetic oils contain higher-quality chemical additives to enhance vehicle performance.

Hybrid-Vehicle Oil

Hybrid-vehicle engine oil formulations address the unique challenges hybrid vehicles face: 

• Rapid acceleration to high engine speeds
• Constant stop-start driving conditions
• Cooler engine temperatures
• Oil contamination

Note: While some hybrids may use one of the oil types mentioned above, hybrid-vehicle engine oils are NOT recommended for non-hybrid vehicles.

Engine Oil Grades

The Society of Automotive Engineers International (or SAE) developed a rating for engine oil grades that all oil manufacturers use. The rating method uses a combination of numbers and letters seen on the packaging: 10W or 10W-30. Here’s what the SAE Oil Grades alpha-numeric code represents:

• The first number denotes the oil’s viscosity at 0 degrees F. The smaller the number, the better the oil flows in cold temperatures.
• The W stands for winter (not weight).
• The numbers after the W represent a multi-grade oil with viscosity at 100 degrees C. The higher the number, the thicker the oil remains at higher temperatures.

Consult your owner’s manual for your vehicle’s recommended SAE oil grade and type. Using an oil other than the factory-recommended one may void your factory warranty. Additionally, using inappropriate oil can cause extensive engine damage, requiring part repairs and replacements.

Engine Oil Viscosity

Engine oil viscosity is not constant; temperature and pressure will change the viscosity of your oil. When temperatures drop, it can become harder for engine oil to flow, but it becomes easier when temperatures rise. Most modern vehicles that operate in fluctuating climates benefit from using multi-grade oil.

Engine Oil Weight

The oil grade is not the same as the oil weight. Initially, engine oil came only in a single-weight option (mono-grade), like 0W, 5W, 10W, etc. The W  refers to the oil’s behavior at cold (winter) temperatures. The performance of the early mono-grade oils proved insufficient in severe temperatures. Engineers developed multi-weight engine oils to provide more protection over a wider temperature range. 

Seasonal Engine Oil

Auto manufacturers may recommend using seasonal engine oil under specific environmental conditions. For example, vehicles driving in climates that experience exceptionally hot or cold seasonal temperatures may benefit from seasonal engine oil. Read your owner’s manual or discuss options with your technician at your next oil change service to verify if seasonal oil will benefit your vehicle.

Chemical Additives

All engine oils contain chemical additives to aid the base oil in decreasing friction, dissipating heat, reducing corrosion, and preventing sludge formation. Complex engineering and rigorous testing of these chemical additives determine the ones that perform the best for each oil grade.

Auto Maintenance: Oil Change Intervals

When it comes to auto maintenance, there is no longer a ‘universal standard’ to which all vehicles adhere. Modern automobiles come in such a wide variety of styles that oil change intervals also vary widely. Knowing the oil type your vehicle requires can narrow the auto maintenance service interval a bit. Keep in mind that commercial, diesel, and heavy-duty vehicles may have other factors that impact their oil change intervals. Therefore, always read and follow the guidelines outlined in your owner’s manual for your specific make, model, and year vehicle.

• Conventional Oil: This type provides less protection than other oil types, so oil change intervals typically occur every 3,000 – 5,000 miles.

• Synthetic-Blend Oil: Lasts longer than conventional oils but not as long as full-synthetic oils. Oil change intervals are typically every 7,500 miles.

• Full-Synthetic Oil: Provides high protection, so oil change intervals are typically every 10,000 – 25,000 miles.

• Hybrid-Vehicle Oil: Varies by manufacturer, so it is not yet a one-size-fits-all product. Different hybrid vehicles may use different types of engine oil, so it’s vital only to use the oil recommended by the manufacturer. The oil change intervals will also vary depending on the oil type and grade used. Always read your owner’s manual for the time and mileage markers for your hybrid vehicle’s oil change service schedule.

Oil Filter

Let’s not forget the oil filter! The oil filter removes contaminants and maintains the necessary oil pressure for vehicle performance. An oil filter literally traps harmful particulates like dirt, metal particles, and other debris in used engine oil. Without a clean filter, the debris in your oil can damage your vehicle’s engine and other components. Most auto manufacturers recommend a new oil filter with every oil change service. 

Schedule Oil Change Service in Kirkland WA

Trust Fisher’s Auto Service‘s team of ASE-certified and Master mechanics for all your auto maintenance needs. We will quickly change your engine oil and oil filter to get you back on the road. We have worked in the Kirkland area since 1979–a genuine testament to our honest and friendly work. 

Call us at (425) 441-3601 or visit us online to make an appointment for your next oil change service.