5W50 or 10W40..??

LiquidZ · 05-28-2010, 08:37 AM

As a rule of thumb, you can increase your viscosity level by 1 ( going from 5W-30 to 5W-40). However, I don't feel comfortable doing this on new engines as their close tolerances might not allow for adequate lubrication with a thicker oil.

Also, there is no such thing as too thin of an oil on startup. Even if you are in Panama where you have really high temperatures, your engine will always pump an oil with a lower "winter" number (the 5 in 5W-30) better. Startup is where a lot of wear occurs as parts aren't fully protected by oil.

So I guess what I'm trying to say is that I see no reason why you shouldn't stick with 5W-30. By going with a high quality synthetic, you'll be more than covered in your application.

05-28-2010, 08:37 AM	#3 (permalink)
LiquidZ A True Z Fanatic Join Date: Nov 2008 Location: Columbus, OH Posts: 1,940 Drives: Mag. Black 2009 370Z Rep Power: 705	As a rule of thumb, you can increase your viscosity level by 1 ( going from 5W-30 to 5W-40). However, I don't feel comfortable doing this on new engines as their close tolerances might not allow for adequate lubrication with a thicker oil. Also, there is no such thing as too thin of an oil on startup. Even if you are in Panama where you have really high temperatures, your engine will always pump an oil with a lower "winter" number (the 5 in 5W-30) better. Startup is where a lot of wear occurs as parts aren't fully protected by oil. So I guess what I'm trying to say is that I see no reason why you shouldn't stick with 5W-30. By going with a high quality synthetic, you'll be more than covered in your application. __________________ Last edited by LiquidZ; 05-28-2010 at 08:48 AM.