Rotella T5 10w-30, 10,538 miles, 05 Grand Am

[92saturnsl2]

Originally Posted By: friendly_jacek
Fine, show me all those normal UOA that show 1ppm Pb/1000 miles. All mine showed 0ppm/1000 miles. Is that abnormal?


Two engines with entirely different maintenance histories, driving style, weather conditions, the list goes on and on. If you only have 0 or 1 ppm of lead each UOA, congratulations. WAY too many variables to declare that your results represent normal wear, while the 10 PPM in this sample doesn't.

I'm not sure the purpose of arguing over this.. I think it's counter-productive to have this thread evolve into a [censored] contest.

 

[cchase]

Originally Posted By: friendly_jacek
Originally Posted By: dave1251
Originally Posted By: friendly_jacek
Originally Posted By: skyship
Did the lab give you a set of universal averages?? It's difficult to interpret UOA results without knowing what is normal.


Lead is not normal here. Way too high.


1 PPM per 1K miles. I have to disagree. Not a bad report IMO.


You realize we talk about lead and not iron, right?

90+% of UOAs here have lead at 0 regardless of miles.



Some engines don't have any lead in the bearings - which of course would probably show as 0 ppm on a UOA barring some kind of other point source.

Of my many UOA's, I don't think any have come back with 0 lead. My truck routinely spits out double digit lead numbers on shorter OCI's than this. 10 ppm lead on a 10k OCI is a non-issue.

 

[sdan27]

Both UOAs I listed were basically over 12 months. We don't typically drive this vehicle during the winter months as we have another vehicle that handles the snow much better. I don't really feel 10ppm lead is very high given the mileage. I would have to see high lead numbers on at least a few consecutive UOAs to really worry about it. Polaris Labs does not typically offer average wear numbers but they did not list any concern over the lead numbers even being at a minor level. Since we don't drive this vehicle in the bitter cold months, I don't worry about the oil being a 10w instead of the recommended 5w. The 'change oil' light typically comes on around 7-8000 miles.

 

[Clevy]

Originally Posted By: friendly_jacek
Originally Posted By: dave1251
Originally Posted By: friendly_jacek
Originally Posted By: skyship
Did the lab give you a set of universal averages?? It's difficult to interpret UOA results without knowing what is normal.


Lead is not normal here. Way too high.


1 PPM per 1K miles. I have to disagree. Not a bad report IMO.


You realize we talk about lead and not iron, right?

90+% of UOAs here have lead at 0 regardless of miles.



Sure. But those engines aren't using lead in the bearings.
I've been hoping to see this stuff in service. Looks like it did well for the miles

 

[A_Harman]

I think that's an excellent report as far as wear metals are concerned. It's interesting that RT5 has such low Mg and high Ca compared to Rt6. That's abnormal for Rotella's.

 

[mr_diy]

I would say Fe, Pb, and Cu seem high though maybe not out of line for this GM engine. The only normal number is the Al. I would look for results on a similar engine and check that if sodium is high for this oil.

 

[steve20]

if it were mine, I'd stick with the 8K OCI-the increase in wear metals going to 10K OCI isn't worth it ---to me--- at least