Pontiac GTP L67 3800 PP 5w30 5.4k

[ATS-V]

A little background, this engine has for years had slight coolant seepage (lower gaskets). In mid 2010 the vehicle usage had changed from a daily driver to a short tripper.

In early 2013 the upper manifold gasket developed a vacuum leak so at this time I did lower intake gaskets and buttoned it all up. Care was taken to not let any coolant into valve galley and a quart of oil was poured down galley as a precaution. Oil was changed with the cheapest I could find (Peak 5w30 IIRC) and ran for 500 miles. This analysis is the second change after the Peak oil. From my research the Peak uses sodium as an additive
although I can't seem find how much. I also haven't added a drop of coolant since the repair.

I'm a little surprised that Sodium and iron numbers. Questions/comments welcomed.

Code:


OIL TYPE PP PP PP PP PP PP GC GC GC GC M1 M1 M1 M1-EP M1 M1 M1 M1

OIL GRADE 5w30 5w30 5w30 10w30 5w30 5w30 0W30 0W30 0w30 0w30 5w30* 5w30* 5w30 5w30 5w30 10w30 5w30 10w30

MILES IN USE 5.4k 5.6k 4.9k 4.5k 4.4k 4.6k 4.4k 4.3k 4.4k 4.6k 4.8k 5.5k 5.7k 5.6k 6.2k 8.7k 7k 5k Uni Avg

MILES 223.7k 207.9k 191.9k 182.2k 177.7k 173.3k 164.8k 156.8k 152.5k 148.1k 143.5k 138.7k 133.2k 128k 121.9k 115.7k 107k 95k

SAMPLE TAKEN 8/31/14 4/27/12 3/19/10 7/26/09 4/19/09 1/23/09 8/2/08 2/9/08 10/27/07 7/21/07 4/7/07 1/6/07 9/2/06 5/7/06 1/7/06 8/21/05 2/28/05 6/6/04



ALUMINUM 3 4 2 3 2 3 2 3 2 3 4 3 2 2 3 2 2 2 3

CHROMIUM 0 1 1 0 0 1 1 1 0 1 1 1 0 1 1 1 1 1 1

IRON 50 34 11 8 9 13 12 14 12 17 24 19 14 16 22 18 17 13 14

COPPER 13 13 11 15 9 12 12 14 14 13 12 14 14 13 15 17 13 16 18

LEAD 9 11 5 5 4 8 18 14 22 19 10 14 28 11 23 42 5 5 7

TIN 0 0 0 0 1 1 0 2 0 0 0 0 1 0 0 1 2 1 1

MOLYBDENUM 54 47 53 54 53 50 3 2 6 18 91 84 82 72 85 77 60 70 41

NICKEL 0 1 1 1 0 1 1 1 0 1 1 2 0 0 1 0 0 1 0

MANGANESE 1 1 1 2 0 0 1 0 0 0 0 1 1 0 0 0 0 0 0

SILVER 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

TITANIUM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

POTASSIUM 9 9 8 12 17 22 9 16 6 10 20 9 6 6 11 17 11 7 7

BORON 3 23 25 30 26 25 4 3 5 12 57 60 51 122 55 106 104 150 45

SILICON 14 11 7 7 5 7 8 8 7 9 11 11 11 11 12 9 9 11 11

SODIUM 31 42 39 26 36 48 23 35 19 24 46 20 6 9 10 14 12 19 11

CALCIUM 2379 3076 3277 3026 3067 3267 2494 1896 1866 2013 2564 2308 2731 2294 2705 2780 2302 3134 2128

MAGNESIUM 17 16 17 22 34 131 593 563 525 424 20 15 14 19 19 19 25 23 131

PHOSPHORUS 698 656 697 742 703 766 981 870 842 797 737 658 673 698 677 745 592 831 741

ZINC 874 759 915 979 870 1082 1251 1066 1082 1041 932 818 834 870 838 946 694 983 901

BARIUM 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0





INSOLUBLES 0.1 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.4 0.3 0.3 0.3 0.3 0.3 0.3 0.4 0.4 0.5

WATER 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.1 0

FLASHPOINT ºF 400 405 390 420 400 385 405 415 415 395 405 395 390 370 395 425 385 375

SUS VIS 210ºF 57.6 58 60.9 60.7 59.5 61 66.9 67.7 66.8 67.7 63.6 64.4 63.2 62.5 61.8 65.3 63 62.2

cSt VIS 100°C 9.54 9.64 10.47 10.41 10.08 10.51 12.13 12.35 12.11 12.33 11.22 11.44 11.11 10.91 10.7 11.68 11.05 10.8





* 4 qts M1 5w30 + 1 qt M1-EP 15w50

 

[dustyroads]

I don't know what to say. Your potassium and sodium levels both match up with a good long trend of analyses, no spike in those two. Not sure what happened with the iron.

Your sodium level does not indicate previous use of an add-pack with sodium in it. After using an oil with 300-500 ppm of sodium, the residual is often well over 100 ppm in the next sample. Maybe your engine drains exceptionally well, but I doubt you used a sodium laced oil just before this run. (?)

The silicon is slightly higher but not bad overall. I only see a jump in iron but don't know why.

 

[dustyroads]

Looking again, I see it was over two years and almost 16k since the last report. Maybe you had a large amount of iron built up from the coolant intrusion and you are seeing residual iron.

Maybe your next sample's iron will come back down after another oci.

I guess you may never have had any coolant intrusion? I just don't know.

 

[ATS-V]

I repaired the LIM gaskets and cheap Peak Oil was run for 500 miles. Then a fill of PP 5w30, then another PP 5w30 which is the sample above. Repair was done March 2013.

Regarding your coolant intrusion comment, it was very, very minor that's the reason I never ripped into it until 2013. Whenever I saw external seepage I added GM seal tabs to keep it in check.

It's hard to say, prior to 2010 this engine saw the same routine averaging 16k per year. Now it sees only 6k per year and lots of short trips which I believe is the source of the iron (many more cold starts per mile).

All in all this engine doesn't owe me anything, it's one of the most trouble free engines I have ever owned. It still puts down good power and averages good mileage if I can say out of it (it has a few mods).


Originally Posted By: dustyroads
Looking again, I see it was over two years and almost 16k since the last report. Maybe you had a large amount of iron built up from the coolant intrusion and you are seeing residual iron.

Maybe your next sample's iron will come back down after another oci.

I guess you may never have had any coolant intrusion? I just don't know.

 

[dustyroads]

The short trips make sense for the rise in iron. I thought maybe your oil was getting contaminated and causing iron to go higher but short tripping and cold starts sounds plausible. My dad's 5.3 had a couple real ugly reports from super short trips and many cold starts.