Is 0w20 always interchangeable with 5w20?

[jake88]

It is hard for me to imagine why you would not be able to make that change in a situation where the OE calls for a GF-5 mineral oil or blend. However, with DEXOS the volatility limit is lower (13% v 15%).

A typical DEXOS rated 5W-20 may have a NOACK of 11% while a GF-5 0W-20 may have a NOACK of 14%. With long drains that means more consumption and evaporative thickening with the 0W-20 oil.

 

[CATERHAM]

Originally Posted By: jake88

A typical DEXOS rated 5W-20 may have a NOACK of 11% while a GF-5 0W-20 may have a NOACK of 14%. With long drains that means more consumption and evaporative thickening with the 0W-20 oil.

In theory that's true plus the fact that the 5W-20 is a heavier oil. But remember NOACK is measured at 250C.
The 3% difference may have a more noticeable effect if you're seeing very high oil temp's but with average maximum oil sump temp's of 90C for most 20wt and 30wt applications it's insignificant.

 

[Silverado12]

Originally Posted By: cp3
Originally Posted By: Silverado12
My 2010 3.5 H.O. in my Challenger calls for 10W instead of 5W, so I wouldn't assume that 0W would substitute for 5W. FWIW I use 10W-30 in my Silverado also, which calls for 5W. I don't think it's an extremely big deal, though.


AH but would 10wXX always substitute for 5wXX?

Do you have any UOAs on your 3.5? Curious if it has a tendency to shear.


No UOA's. I just buy one type of oil (10W-30 Shell from the Costco). That's the reason why I use 10W in the Silverado. I'm within the temp specs of 10W here in VA.

 

[Shannow]

I don't get what all the confusion is regarding 20s....