97 Pontiac GTP L67 3800, GC 0w30 4.4k

[ATS-V]

Latest and last fill of GC. There was a missing interval that I did not sample due to trying to eliminate a lean condition DTC that was periodically popping up. Oil was changed 1 week after problem (various small vacuum leaks) was resolved. Coolant leak has subsided, haven't added any more. For those that have a keen eye this fill had one quart of green in it.

Looking for advise on next fill and why?

Code:
OIL GC0W30 GC0W30 GC0w30 GC0w30 M15w30* M15w30* M15w30

MILES IN USE 4.4k 4.3k 4.4k 4.6k 4.8k 5.5k 5.7k

MILES 164.8k 156.8k 152.5k 148.1k 143.5k 138.7k 133.2k

SAMPLE TAKEN 8/2/08 2/9/08 10/27/07 7/21/07 4/7/07 1/6/07 9/2/06



ALUMINUM 2 3 2 3 4 3 2

CHROMIUM 1 1 0 1 1 1 0

IRON 12 14 12 17 24 19 14

COPPER 12 14 14 13 12 14 14

LEAD 18 14 22 19 10 14 28

TIN 0 2 0 0 0 0 1

MOLYBDENUM 3 2 6 18 91 84 82

NICKEL 1 1 0 1 1 2 0

MANGANESE 1 0 0 0 0 1 1

SILVER 0 0 0 0 0 0 0

TITANIUM 0 0 0 0 0 0 0

POTASSIUM 9 16 6 10 20 9 6

BORON 4 3 5 12 57 60 51

SILICON 8 8 7 9 11 11 11

SODIUM 23 35 19 24 46 20 6

CALCIUM 2494 1896 1866 2013 2564 2308 2731

MAGNESIUM 593 563 525 424 20 15 14

PHOSPHORUS 981 870 842 797 737 658 673

ZINC 1251 1066 1082 1041 932 818 834

BARIUM 0 0 0 0 0 0 0





INSOLUBLES 0.3 0.3 0.4 0.3 0.3 0.3 0.3

WATER 0 0 0 0 0 0 0

FLASHPOINT ºF 405 415 415 395 405 395 390

SUS VIS 210ºF 66.9 67.7 66.8 67.7 63.6 64.4 63.2





* 4 qts M1 5w30 + 1 qt M1EP 15w50


Code:


OIL M15w30EP M15w30 M110w30 M15w30 M110w30

MILES IN USE 5.6k 6.2k 8.7k 7k 5k Uni Avg

MILES 128k 121.9k 115.7k 107k 95k

SAMPLE TAKEN 5/7/06 1/7/06 8/21/05 2/28/05 6/6/04



ALUMINUM 2 3 2 2 2 3

CHROMIUM 1 1 1 1 1 1

IRON 16 22 18 17 13 14

COPPER 13 15 17 13 16 18

LEAD 11 23 42 5 5 7

TIN 0 0 1 2 1 1

MOLYBDENUM 72 85 77 60 70 41

NICKEL 0 1 0 0 1 0

MANGANESE 0 0 0 0 0 0

SILVER 0 0 0 0 0 0

TITANIUM 0 0 0 0 0 0

POTASSIUM 6 11 17 11 7 7

BORON 122 55 106 104 150 45

SILICON 11 12 9 9 11 11

SODIUM 9 10 14 12 19 11

CALCIUM 2294 2705 2780 2302 3134 2128

MAGNESIUM 19 19 19 25 23 131

PHOSPHORUS 698 677 745 592 831 741

ZINC 870 838 946 694 983 901

BARIUM 0 0 0 0 0





INSOLUBLES 0.3 0.3 0.4 0.4 0.5

WATER 0 0 0 0.1 0

FLASHPOINT ºF 370 395 425 385 375

SUS VIS 210ºF 62.5 61.8 65.3 63 62.2

cSt @ 212ºF 10.91 10.7 11.68 11.05 10.8

 

[pickled]

Take it FWIW, but it Looks like you are into the bearings a little bit...that streak from around 115k should have stopped contributing by now. Your fuel dilution looks great though so life is good there. Do you have a heavy driving style...what's you typical commute like? I'd look at an oil like Amsoil ACD or a Rotella/Delo 5W40 syn for your next interval. These oils flow well in cold weather and still control wear like no other. They may help slow down your lead and copper migration. Good luck! :2cents:

 

[glennc]

It seems to me that it is not uncommon for GC to have higher lead than normal. I don't know if it's a problem with the oil or more like the aggressive cleaning that Redline is said to do. AFAIK GC is not considered to have much if any Grp V, but I could be mistaken about that.

In this case, though, I am assuming that throughout most of this history you have had issues with coolant getting into the oil, and that is more likely contributing to higher than normal wear. The engine might last a long time like this, but do you know what the problem is and have you thought about fixing it? I'm guessing that is also the reason for your short OCIs.

 

[FZ1]

Keep the oci in the 4k range to keep the oil "fresh".

 

[ATS-V]

I think the next fill will be a 5w40 and then analysis to confirm my suspicions.