by Pat Goss
Pat Goss and Thom Smith
Whether it’s 60 horsepower or 600 horsepower, the life blood of every engine is its oil, and joining us to talk about oils is Thom Smith. Thom, you are an oil chemist right?
THOM SMITH: Yes.
GOSS: In that capacity, what do you do?
SMITH: What I do is I formulate the oils for your engines, your transmissions; I select the appropriate base oils and additive systems to give you the proper performance in your vehicle.
GOSS: So oils today are engineered, they’re not just pumped out of the ground and into the engine?
SMITH: No, definitely not. There’s a lot that goes into making an oil. You start with base oils, and that’s the part that comes out of the ground or may be synthesized, and you take the crude oil out of the ground and you have to go through several series of processes to get a base fluid that’s adequate to meet the needs of an engine, but even that isn’t everything that your engine needs. You’ve got to put anti-oxidants in it, detergents in it, dispersants, anti-wear agents, friction modifiers, a whole array of different components to give you the performance that’s needed in a modern engine today.
GOSS: So it’s a real cocktail of different things?
SMITH: It’s a real cocktail, and it’s the balance of those ingredients that is very important.
GOSS: One of the things that I get a lot of questions on, people say “Well, I took my car in for an oil change and my manual says that it should have 5w-20 but the technician told me I should use 15w 40,” or something like that.
SMITH: No, you should use what the owner’s manual recommends. The engines have been designed to run on the viscosity that’s recommended in your owner’s manual. If you use too heavy of an oil in the vehicle you’re not going to get the horsepower or the fuel efficiency out of it. And if you use too light of an oil you may not get the protection you need.
GOSS: So always use the viscosity that the manufacturer recommends. What about oil qualities and types?
SMITH: Well there are several different types of oils out on the marketplace: you have conventional for the standard motorist, you have a semi-synthetic to give a little more protection, you have a full synthetic to give the ultimate in protection, and you also have specialty oils like high-mileage oils for engines with high mileage. These are formulated with additional components such as seal conditioners because seals can shrink and become brittle, and extra anti-wear agents, things that an older engine will need.
GOSS: OK, oil filter, always change it?
SMITH: Always change the oil filter! The oil filter is collecting a lot of the contaminants that come from combustion and you’ve got to get those out of there.
GOSS: And quality is important, don’t look for the cheapest price?
SMITH: And that goes for everything, you didn’t do that when you bought your car, don’t do it when you buy you oil or filter.
If you have a question or comment, write to me.
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