Can I use 5w-30 instead?

[MSke390]

Sorry I was referring to them saying that synthetic is the recommended oil to use in this car when it's not. I understand that times are tough for many now but all I ask is to be ethical.

 

[ceric]

In fact, more and more automakers are recommending synthetic oil for their vehicles.
Especially so for hybrids.
And, why not? Dealers are the ones that makes money. They get to charge you $50-$60 instead of $30.

 

[Interiorman]

I use Mobil 1 0W40......After having is as my factory fill on my GT-R and running the car hard on the track with 10,000km oil change intervals and seeing no significant concerns via oil analysis, I figured if its good after taking such a beating, it will do well in a daily driven CX-9. I've found fuel economy is about the same as when using Mobil 1 5W20.

 

[blackntan]

Good info. I'm definitely no oil expert, but I've read a couple oil threads and what not, and am still trying to learn.

It is my understanding that the manufacturers these days are recommending the lower operating temp viscosities (20, etc.) in order to get the best mpg out of the motors. It's also my understanding (correct me if I'm wrong), that it is ok, if not better, to run a slightly higher operating temp viscosity (30, 40) in those same motors? If anything, you may lose a fraction of the mpg that the manufacturer claims (because they used 20 when testing), but get a little better protection? In all of my cursory research, you will not damage a motor that calls for (recommends) 0w-20 or 5w-20, if you use 0w-30 or 0w-40...I think? I'm still not sure of the significance of the 0w vs. 5w. I think it is the viscosity of the oil when it is cold, but I'm not sure if it has any significance, especially living in the warm state of FL. (my other vehicle "recommends" 0w-20 or 5w-20, so I figure the significance of the first number is minimal, if anything at all). At any rate, I'm going to be running the synthetic Castrol 0w-30, which is supposedly a thick 30, almost 40, and be tracking my MPG's over the next several months/year, and get the oil analyzed to see what is going on with the oil and the motor. If I'm satisfied, I'll keep running it.

I use Mobil 1 0W40......After having is as my factory fill on my GT-R and running the car hard on the track with 10,000km oil change intervals and seeing no significant concerns via oil analysis, I figured if its good after taking such a beating, it will do well in a daily driven CX-9. I've found fuel economy is about the same as when using Mobil 1 5W20.

 

[Interiorman]

Good info. I'm definitely no oil expert, but I've read a couple oil threads and what not, and am still trying to learn.

It is my understanding that the manufacturers these days are recommending the lower operating temp viscosities (20, etc.) in order to get the best mpg out of the motors. It's also my understanding (correct me if I'm wrong), that it is ok, if not better, to run a slightly higher operating temp viscosity (30, 40) in those same motors? If anything, you may lose a fraction of the mpg that the manufacturer claims (because they used 20 when testing), but get a little better protection? In all of my cursory research, you will not damage a motor that calls for (recommends) 0w-20 or 5w-20, if you use 0w-30 or 0w-40...I think? I'm still not sure of the significance of the 0w vs. 5w. I think it is the viscosity of the oil when it is cold, but I'm not sure if it has any significance, especially living in the warm state of FL. (my other vehicle "recommends" 0w-20 or 5w-20, so I figure the significance of the first number is minimal, if anything at all). At any rate, I'm going to be running the synthetic Castrol 0w-30, which is supposedly a thick 30, almost 40, and be tracking my MPG's over the next several months/year, and get the oil analyzed to see what is going on with the oil and the motor. If I'm satisfied, I'll keep running it.

The first number indicates the oils ability to flow when cold. The lower the number the better it flows in cold temps (during start up). Living in Florida, there really is not need to worry about that, even a 10W will be great. In fact when the summer months come, I'd use 20W50 or 10W40. The second number tells you how well the oil will deal with heat (the higher the number the better the protection).

Remember for daily driven cars your car your biggest concern is during startup (when most of the wear occurs). If the oil is really thin and out temps are high, then the oil will not hold to well against the metal parts during start up. Thin oil is designed to flow better in the cold, but that works against you in hot temps.