When I got my first car, I knew nothing – I mean absolutely nothing – about cars. All I knew was that I needed to keep it full of gas and that I should get the oil changed according to the sticker in my windshield. I remember going to the oil change for the first several years (yes, several!) and having no idea what kind of oil to put in my car. The guy would ask which weight I wanted and I had no clue what he was even talking about. I didn’t know anything about weight, grade, or manufacturers. If I had a good mechanic, I should not have had to. However, here’s a very basic run-down of a very complicated aspect of your vehicle’s regular maintenance. Hopefully it will save you from some of the confusion I had as a young vehicle owner.

I recently shared information on finding the proper gasoline for your vehicle, and while there are very specific regulations in place for fuel grades, this is not true for engine oil. The science behind engine oil is rather complex and, while Andrew is really good at explaining it to those who want to know, it goes over my head even though I’ve heard it a hundred times before. Here are the bare basics as I understand it. Please get in touch with Andrew if you are interested in a more detailed explanation.

The Bare Basics on Motor Oil Grade and Weight

The American market for motor oil offers oil grades labeled as “conventional,” “synthetic blend,” and “synthetic.” Conventional grade motor oil is derived directly from crude oil. Synthetic grade motor oil is refined conventional oil that is distilled and broken down into a cleaner product, which is a good thing for your vehicle’s engine. But don’t just go by the label. What you see is not necessarily what you get, as many times what the label says is purely for marketing purposes and what is labeled as “synthetic” may actually be a synthetic blend of varying degrees.

In addition to the grade is the oil weight, or viscosity, of the oil. The weight of the oil you use in your vehicle should always be the same. For example, you don’t use 5W30 one time and then 5W20 the next oil change. The only exception is if you live in a climate that gets below freezing on a regular basis. In that instance, you would use a different weight (as directed in your Owner’s Manual) during those months than the months that are regularly above freezing.

Confused? It’s ok. Look in your owner’s manual and stick with what weight and grade your vehicle’s manufacturer formulates (i.e. If you have a Toyota and your vehicle’s manual says to use 5W30 weight, use Toyota 5W30 oil), but don’t hesitate to talk to your mechanic about cost effective options of equal or greater quality keeping in mind that not all oil is created equally. This is why it’s important to have a mechanic whom you can trust to do quality work with quality products.

It’s Not Just About Oil

The good news about the confusing marketing ploys of the oil industry is that we don’t rely on the oil grade alone to keep your vehicle in good condition. Another important aspect of changing your vehicle’s oil is also changing the engine oil filter. By replacing the filter with a new properly fitted high quality filter each time you change your oil, you are ensuring removal of any debris from the oil before it gets into your engine. As with the oil, be sure the filter is the proper size and a quality equal to or better than the filter that the manufacturer designed for the vehicle.

Proper installation is also important. A lot of people think that changing oil is a rather simple process once getting the proper oil and filter. However, the number of times we’ve seen vehicle’s in our shop with oil drain plugs and oil filters that were improperly installed into the vehicle is surprising. These issues don’t just come up with DIYers, but also improperly trained mechanics (be wary of anywhere that promises fast and cheap – you get what you pay for). This can cause costly damage to the vehicle, so it’s worth it spend a little now to save a little later by having a professional whom you trust do the work.

The Importance of Oil Change Intervals

One final note on engine oil – you can use the highest quality oil and filter installed by a professional trusted mechanic but still risk damage to your engine if you do not adhere to a proper interval between changes. Just because the bottle says you can go longer between oil changes, doesn’t mean that it’s a good idea to do so.

The interval will vary based on the make and model of your vehicle and your driving conditions. Each vehicle manufacturer offers a range of mileage acceptable for your specific vehicle. You’ll want to stick to the lower end of the range if you are taking a lot of short trips (5 minutes or so) or driving in a lot of heavy stop and go traffic (like downtown city driving). You can stretch to the upper end of the range if you do a lot of long trips, like on long stretches of highway. It’s always better to use a mileage interval than a time interval for this reason. But don’t just guess, talk to a trusted mechanic about your driving conditions and he or she can help you determine what an appropriate interval is for your vehicle. The good news is that newer vehicles often have an oil quality indicator which is generally pretty accurate – when you get to about 15% quality, it’s time to make an appointment for an oil change.

There is a lot of information about oil out there – some of it is accurate and some is not and it’s a lot to sort through. Believe me, just researching it gave me a headache! This is why having a mechanic you trust and have a relationship with is important for maintaining for vehicle well. Just like eating a healthy balanced diet is important for our overall health and well-being, using the right oil is also important for the health and wellbeing of your vehicle. If you trust the expert (your mechanic) and invest wisely in putting the right stuff in your vehicle now, you’ll get a better and longer life out of your vehicle down the road.

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Marinelli Auto Service is an auto repair shop in Winter Park, Florida. We’ve been serving Central Florida since 2015. We provide maintenance and repairs for a variety of makes and models.