I know they recommend 0W-20 for the 2014 IS350 F-Sport, but I live in South Florida and was thinking of using Royal Purple's HPS 5W-30. There are times I drive the car hard, and I was thinking the Royal Purple might be a good choice. The Owner's Manual (page 503) says "an oil with higher viscosity may be suited for a vehicle that operates at high speeds or under extreme loads." Wondering if anyone has made the switch?https://www.clublexus.com/forums/images/smilies/pat.gif

 

I tried 5-30 Mobil one for about 5K miles. Then the dealer performed 10K maintenance with 0-20 toyota's oil and the only big difference that I noticed was a gas mileage improved with 0-20 oil by about 1-2 MPG average. So I decided to stick to what the manufacturer recommends.

 

Great to know, thanks!