Been trying to gather information on Royal Purple 5w40.
And found a lot of people saying that its not to good for Vq engines?is that true,if yes whats the reason

2004 g35
180000km
diving style-very spirited

 

Not true, people were basing info on oil analysis info....royal purple actually did well there are some others that people liked better though. The only way to really know is to do an oil analysis yourself and see how it is for your car.

 

Thank you for the answer,and what is your opinion on 5w40 vs 5w30?