2002 Camaro LS1, GC 0w30, 8700 miles

[A_Harman]

From Polaris Labs.
8700 miles on oil, 218000 miles on vehicle
Wear Metals
(Element: 193k-RL 5w30, 200k-LS30, 209k-PU 5w30, 218K-GC 0w30)
Fe: 103, 33, 27, 16
Al: 16, 10, 9, 5
Cu: 34, 29, 11, 11
Pb: 24, 3, 3, 2
Sn: 5, 2, 1, 0

Contaminant Metals
Si: 21, 15, 12, 11
Na: 20, 40, 21, 12

Multi-source Metals
Mo: 535, 160, 62, 10
B: 27, 8, 40, 5

Additive Metals
Mg: 105, 252, 55, 474
Ca: 2464, 2624, 2428, 1893
P: 1076, 1001, 783, 840
Zn: 1403, 1277, 945, 1071

Fuel dilution: Soot: Water:
3.5 qts. added during OCI
KV100: 11.6, 12.2, 12.2, 12.7
TBN: 2.64, 2.44, 2.69, 4.13
Oxidation: 109, 101, 31, 16
Nitration: 15, 18, 16, 17

Polaris Comments: Data flagged for presence of Magnesium and viscosity out of grade (high). No immediate need for maintenance action.

German Castrol may have been noisy in the engine, but turned in a good UOA. It has the best TBN retention of the oils I've run so far. This oil had a lot of life left when I drained it. Sadly, it seems the engine has settled at an oil consumption rate of 2500 miles/qt. In the good old days, it was 6000 miles/qt. The oil wasn't really stressed during the OCI, however. No track days, just daily driving and highway cruising.

The new oil fill is a 50/50 mix of PU 5w30 and PUE 5w40. I still think I'll be taking it to track days this year, so I put in a thicker blend.

 

[901Memphis]

Everything looks good now.

That must have been a track day with the first UOA on Redline, you shed some GM metal there.

 

[CATERHAM]

The wear metals have been trending down since the storage related episode with RL.

It is possible that the lack of any track days contributed to the lower wear metals. It would be interesting to know the maximum oil temp's and minimum OP at high rev's for each UOA session if you have it?

 

[A_Harman]

Not for the Camaro. I don't have a datalogging system in it. I just check the oil before each lapping session and top it up if necessary. The factory gauge package has oil pressure, but not oil temperature. I have seen the oil pressure as low as 30 psi on the straightaways on a hot day with M1 5w30 that had been diluted with fuel. I dumped that oil immediately when I got home. Normal straightaway oil pressure with the oil hot is about 40 psi. I can't monitor oil pressure for minimum in the turns because my eyes are up, sighting through the turn and down the next straight.

 

[CATERHAM]

Originally Posted By: A_Harman
I can't monitor oil pressure for minimum in the turns because my eyes are up, sighting through the turn and down the next straight.

I hear ya but that of course is only neccessary to check for oil starvation. And it certainly helps if the gauge is large and located high on the dash so that it is just a split second glance without hardly moving your head. If the gauge is low down on the console in front of the gearshift it's when you're cornering at the limit in a high speed corner.

30 psi at high rev's in a Chevy would represent a very low operational viscosity I would think in bearing wiping territory at WOT. I guess you didn't keep a sample of the dumped oil to have a UOA done?

 

[A_Harman]

No, the overheating and fuel dilution incident was in 2009, before I started doing UOA's. That was when the car only had about 110,000 miles. I've done a few bad things to the Camaro over its lifetime, but so far it's survived it all.

 

[CATERHAM]

Well that just goes to show how difficult it is to run an oil that's "too light" which results in actual measurable engine wear even though you would think the situation was primed to do so.

It reminds me of an SAE paper I posted a few years ago where they ran a bespoke 0W-5 (estimated HTHSV of 1.7cP) with a typical DI package in a GM V6 truck for about 20,000 miles IIRC on the street.
They made a point of mentioning the truck wasn't babied in any way and they did an number of WOT runs from stop lights, that sort of stuff. When they tore the engine down there was no measurable wear.