OK I went to change my oil and went to the autozone and couldn't find 6 quarts of my usual Mobil 1 Super Synthetic 10W-30 but I saw some Mobil 15W-50 Super Synthetic Performance Driving Oil...I figured it wasn't a big deal and changed my oil to that. Car's been running great now for a few days with no problems but I just wanted to make sure this oil was ok for the close tollerances of the F20C. Has anyone else used this oil yet??? Also I live in Phoenix and it's never cold and of course it's very hot down here so I figured the 50 would give me a batter viscosity and cool my engine more...Opinions?

 

I was going to put 5W-50 in my car, but the dealer said it would be too viscous for the engine.

 

FWIW, I have been able to find Mobil 1 10W-30 at WalMart in a 5-quart container on several occasions.

 

While 3,000 miles with 15W50 will likely do no damage, I'd stick to 10W30 if at all possible.

 

Synthetic oils don't seem get thick when it's cold, I doubt they'll actually be more viscous to the point of any damage (lack of lubrication protection.) Having lived in Phoenix, and now out in the middle of the desert, I think we could use the higher weight, especially in the summer. But, I'm not "into" the ins-and-outs of motor oil, and I'll continue to use the recommended 10-30 until I find out differently from an authoritative source. If I was in your situation, I'd let it run until the next oil change nearer to the cooler season.

 

[QUOTE]Originally posted by QPhox4
[B]Synthetic oils don't seem get thick when it's cold, I doubt they'll actually be more viscous to the point of any damage (lack of lubrication protection.)

 

[QUOTE]Originally posted by StwoK
[B]

Most synthetics will pour freely at -40 degrees F regardless of their viscosity rating.

 

Don't sweat it.. you probably have a good oil for an Arizona summer! Just go back to the lower viscosity before winter. People are making something over nothing here..

 

Great...thanks...I was getting really worried there for a sec.

 

Actually higher viscosity would be an oil rated at 0W , 5W , 10W whereas a lower viscosity would be 40 or 50. The lower the number the higher the viscosity or rate of flow. So when the engine&oil heat up, the oil will thicken to its viscosity rating. Our engines rely on temperature and oil pressure to engage VTEC. A thicker oil may lower oil pressure and a thicker oil also offers more resistance. So with a 15W-50 what you might notice is a drop in MPG. When car companies rate their cars for HP, MPG, and EPA ratings it is done with a prescribed oil, in our case 10W-30 for normal use.

Are you hurting anything?? Probably not. At the next oil change switch back to 10W-30.

Cyber Logic, hope this answered your question on viscosity.