5w-20 and copper in a UOA

[nicholas]

I just checked out about 40+ used oil analysis, and did a comparison between the 5w-20's and 5w30's.....

From what I have read, all of the 5w-20 used oil analysis have lower copper readings, actually 90% of the 20 weight used oil analysis are less than 5ppm....
This was also the case with the 0w30 used oil analysis as well.

And most of the 5w30 used oil analysis are above 10-15ppm of copper.

It seems the valve train is "happier" with the lower vis @ 40c oils,

But I am sure most of you around here know this already...

 

[Schmoe]

Valve train is cheaper to fix than replacing a crankshaft.

 

[Pablo]

Quote:

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I just checked out about 40+ used oil analysis, and did a comparison between the 5w-20's and 5w30's.....

From what I have read, all of the 5w-20 used oil analysis have lower copper readings, actually 90% of the 20 weight used oil analysis are less than 5ppm....
This was also the case with the 0w30 used oil analysis as well.

And most of the 5w30 used oil analysis are above 10-15ppm of copper.

It seems the valve train is "happier" with the lower vis @ 40c oils,

But I am sure most of you around here know this already...

---

That's kind of interesting (is it statistically true?) the reason I type that is Honda is the XW-20 pioneer and they typically show lots of copper....

Valve train? Cu comes from lower end bearings, oil coolers, etc, although some cam bearings have Cu alloy wear surfaces.

 

[Pablo]

I did forget about the famous Cu GM cam thrust washer/bearing.