Your vehicle's engine contains moving and sliding parts which operate under extreme heat with a lot of force. These metal parts must be kept lubricated to prevent damage, reduce friction, and maximize the life of your engine. Engine oil circulates constantly through your engine, providing the necessary lubrication.
Why Does the Oil Need To Be Changed?
Over time, your engine oil loses its effectiveness and must be changed.
The extreme heat in your engine makes the oil oxidate and break down. This changes the oil’s chemistry and makes it much less effective.
Oil also thickens over time. Thick, sludgy oil clogs narrow oil passages and prevents oil from reaching vital components, causing them to rub against each other with insufficient lubrication, which is harmful to your engine.
Your oil filter and air filter do their best to keep things clean, but over time contaminants always find their way into your engine oil. Your oil filter removes contaminants as the oil circulates, but eventually the air filter, oil filter and engine oil all get clogged with dirt and need to be changed.
How Often Do I Need To Change My Oil?
Answer #1: In the 20th century, the automotive industry suggested that average drivers with average vehicles and average driving conditions should change their conventional (petroleum-based) oil and filter every 3 months or 3,000 miles.
Are you, your driving habits, driving conditions, and vehicle average? How can you be sure?
Answer #2: When it gets dirty.
21st century automotive manufacturing has led to better parts, less friction, and fewer contaminants over time. Some manufacturers now recommend 5,000 - 7,000 miles between oil changes, but it depends.
- If you drive in harsh conditions (hot climates, dirt roads, hauling a trailer, frequent starts and stops, mostly short trips) you might need to change your oil more frequently.
- If you drive in normal conditions, check your owner's manual and manufacturer recommendations: you might be able to go longer. BUT if you extend the time between oil changes, you MUST check your oil level. Your oil level naturally depletes over time, so going longer between oil changes means you will probably need to occasionally add some oil.
What's the Difference Between Synthetic and Conventional Engine Oils?
Synthetic engine oil is chemically engineered to form pure lubricants. All of its molecules serve a designed purpose - there are no contaminants. Their uniform molecular structures provide better friction-reduction, fuel efficiency, and extreme-temperature performance than conventional lubricants.
Conventional engine oil is a petroleum product, refined from crude oil. Crude oil is not pure. It comes out of the ground mixed with contaminants like sulfur, nitrogen, oxygen and also metallic contaminants like nickel or vanadium. The refining process removes most contaminants, but some remain. The non-oil components interfere with lubrication, and decrease engine performance.
Are Synthetic Engine Oils Better?
Synthetic engine oils are more expensive up front, which is always a consideration, but for many vehicles and driving conditions, they provide superior performance.
Generally speaking, synthetic motor oil will nearly always last longer than conventional oil, saving you time and money. But your specific synthetic oil change interval will depend on several factors, including operating conditions, motor oil quality and personal preference.