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The Garage Professor helps us understand viscosity.

Note: Improvements in performance depend on the vehicle, it’s condition and how it’s used. This video is not intended to imply that all users will experience the same performance gain by upgrading to Royal Purple.


Announcer: It's Cruise Night in Southern California, and the Garage Professor is there.

Sandy: Welcome everyone, and thanks for joining us. Today's topic is viscosity and you. So we headed out on Cruise Night to see how much you knew about the heavy subject of viscosity. Let's take a look

Male 1: Viscosity is the slickness of the oil.

Male 2: Viscosity?

Sandy: Okay. Let me ask you the question . . .

Male 2: Okay.

Sandy: And don't grab my stick.

Male 2: I wouldn't dare grab your stick.

Sandy: In layman's terms . . .

Male 2: Yes?

Sandy: Tell me what viscosity means to you.

Female 1: Does that have something to do with the way the oil is burned?

Female 2: Sounds like something that goes fast.

Male 3: I would say that viscosity has to do with the thickness or the
liquidity of the oil.

Sandy: Speed, burning, slickness, or thickness. Well, the last fellow was right. In simple terms, viscosity is the measure of a liquid's thickness. All right. Let's check out the next question. This is a tough one. How do you spell viscosity?

Male 4: Oh that's easy.

Male 5: Viscosity, V-E-S-C-O-T-Y?

Male 6: V-I-S-C-O-U . . .

Female 1: V-E-S-C-O-S-I, no, no there must be a C in there. Vis . . .

Sandy: Viscosity is spelled V-I-S-C-O-S-I-T-Y. It's a noun, and it seems like a few people need to go back to school. Let's check out the next question. If you're driving in hot, terrible weather, stop and go traffic does viscosity come into play in your choice of motor oils based on your driving conditions?

Male 3: I guess if I'm driving it hard I would want it to be thicker, so it
can last longer in my engine, I think.

Male 5: I'd say so. You don't want it to overheat.

Sandy: So you would use a . . .

Male 5: Low viscosity oil?

Sandy: Would you want to use a higher viscosity oil, or lower viscosity oil in this kind of temperature driving?

Male 6: I think you would want a lower viscosity in the oil so that it would not thin out due to the heat.

Sandy: So someone almost got it. All things being equal, you would want a thicker or higher viscosity oil in extreme temperatures and driving conditions. I run Royal Purple with its proprietary additive technology to prevent oil breakdown and lots of lubrication. Now let's check out the next question. You're out on a hot date. This chick is smoking hot. Do you use a high viscosity oil or low viscosity oil?

Male 6: Definitely going to go with the high viscosity oil.

Sandy: You would be correct.

Male 6: Yes.

Female 2: Higher viscosity level.

Sandy: You would be correct.

Male 7: A higher viscosity oil.

Sandy: Right on.

Male 3: What are we doing?

Sandy: That's not for me to answer.

Male 3: I would go with a high viscosity oil.

Sandy: And why is that?

Male 3: For friction purposes.

Sandy: High temperatures . . .

Male 3: Yes.

Sandy: High heat . . .

Male 3: Yes.

Sandy: Hot passion.

Male 3: There you go.

Sandy: Wow, it seems like everybody knew the right viscosity to use on a hot date. And now let's take a look how to read those automotive viscosity numbers. The SAE number is a simplified scale for viscosity ratings. It's often called weight. In this case, a single weight oil is represented by a single number. This number represents the viscosity at normal operating temperatures. A multi-grade oil has two numbers. In this case, the 20W represents the ability of this oil to be cranked over in your engine at sub-freezing temperatures. It's not at all a 20 weight oil. The real viscosity rating of this oil is a 50 weight, and that is at the recommended operating temperatures. It's just that simple.

And remember, always follow your manufacturer's or engine builders recommendation for oil viscosity. You want to make sure that you're using what's appropriate for your driving style and climate condition, as it may impact your vehicle's performance. That's a quick introduction to oil viscosity. Thanks again for joining us, and be sure to catch us again in the garage with the Garage Professor.

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