0W-40 or 5W-30?

[Garak]

Originally Posted By: nap
What happened to the old favorite here Castrol 0W30 A3/B4? Out of fashion?

Cost, I suppose. Which would you rather buy at CT, 0w-30 A3/B4 at $13 a litre that never goes on special any longer, or the 0w-40 A3/B4 in 5 litres that goes on special every few weeks?

 

[CT8]

Originally Posted By: Pelican
Originally Posted By: ZraHamilton
Is there any reason not to use 0w-40?


Your engine may have not been designed to handle W40-weight and if so the passages may not allow the oil to go through.
could you explain that?

 

[jongies3]

Originally Posted By: Bryanccfshr
I would run a new 5w30 or a 0w40. I am about to put the magnatec 5w30 in my Tacoma and run 0w40 in my 4Runner.

You must not be too worried about warranty on either vehicle I take?

 

[kschachn]

Originally Posted By: Garak
Originally Posted By: nap
What happened to the old favorite here Castrol 0W30 A3/B4? Out of fashion?

Cost, I suppose. Which would you rather buy at CT, 0w-30 A3/B4 at $13 a litre that never goes on special any longer, or the 0w-40 A3/B4 in 5 litres that goes on special every few weeks?

Exactly, and here in the US is about $25 for five quarts at the ubiquitous Walmart.

 

[Cujet]

Originally Posted By: Pelican
Originally Posted By: ZraHamilton
Is there any reason not to use 0w-40?


Your engine may have not been designed to handle W40-weight and if so the passages may not allow the oil to go through.


Absolutely not so. Oil viscosity is very misunderstood. Let's compare some extremely different oils.

0W-30 is 550mm2/s at 32F
10W-60 is 550mm2/s at 62F

Likewise they have the same viscosity at 70c and 90c respectively.

Use the 0W-40 without worry. Your engine will thank you. Many GM engines last longer with slightly higher viscosity and more frequent oil changes vs. the oil life monitor.