Corvette UA0 with Redline 5w30: High Lead

Originally Posted by sprinj76
F-body. 98 Z28



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My last ride, before the one in my sig, was a 250K+ mile (in 16 years since ordered new by me), was a no option, '00 Z28 manual.
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Okay, here is my Blackstone from a couple of days ago. I am relieved to see my iron levels lower. I am doing 2-3 AutoX per month now so am using more oil. Used 1/8 of a quart on last one. And lets not forget my high Lead levels which are now lower than universal averages. So happy I am running Mobil 0w40


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DH
 
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Seems to be all evening out now, which is fine. We still don't have enough data since that last iron bump but I wouldn't worry, as I said before. The engine gets worked. I think General Motors has a rule that their UOAs must throw iron levels that are elevated in comparison to most of the competition, irrespective of engine family.
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Originally Posted by Dirty_Howie
Originally Posted by A_Harman
The OP is obsessing too much over autocrossing an LS7 Corvette for about 30 minutes during a 3000 mile oil change interval.
Relax.
The dry sump system in a C6 Z06 holds a lot of oil, and 1.5 minutes on an autocross course is not long enough to heat the oil to any worrisome temperature.
He could safely run the oil until the OLM says to change it. He could probably even safely use M1 5w30 instead of the 0w40.
The decrease in lead after the switch from Redline to M1 is interesting, but I haven't seen anything in this thread that changes my opinion about the cause since I posted it in 2015.
I wonder about the low Phosphorous readings that Blackstone has been getting (from 7/2016 to 8/2017), and would ask them about it. M1 0w40 should have 1000 ppm. I have noticed that Blackstone's Phosphorous readings are often less than the PDS specs, but not by that much. The Iron wear numbers were low during that period.
The Iron wear rates are all less than 1 ppm per 1000 miles, and that's pretty darn good.


Although I appreciate your input I have no idea where you are getting this "obsession over autoX" from. I used to road race regularly and don't think AutoX compares at all in terms of engine wear. The ONLY thing I was ever concerned about was LEAD level. And the ONLY reason for that was that it likely meant bearing wear. The LS7 is an extremely expensive engine to replace so I feel OCI at 3-4K and closely watching my wear metals is prudent.

And I agree about phos levels but don't see where ou get the iron wear rate calculation from??

Thanks
DH


My goodness this thread had a lot of life after I posted in it back in 2015!

But to answer your most recent question: The Iron wear rate calculation is directly from the data on the report: ppm Iron divided by the oil change interval miles.

I used to track my Camaro regularly on Redline 5w30 and never had a problem with Lead concentration in a UOA. Here is an old UOA from my Camaro on Redline 5w30: https://www.bobistheoilguy.com/foru...e-5w30-ls1-camaro-5800-miles#Post2906981
One of the big differences between your LS7 and my LS1 is that my LS1 doesn't have Titanium rods.

By saying "obsessing over autocrossing", I was trying to encourage you to extend the OCI to the point where the oil life monitor tells you to change it.

I stated long ago that the LS7 has aluminum bearings in it, and that the lead was likely coming from the connecting rod small end bushings. The LS7 has Titanium rods and needs leaded bronze small end bushings. But everybody kept saying it was bearing wear. I think it was the high concentration (500+ppm) of Moly in the Redline leaching Lead out of the rod small end bushings. So it was chemistry, not physics, that was likely causing the elevated Lead readings.
 
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Originally Posted by A_Harman
Originally Posted by Dirty_Howie
Originally Posted by A_Harman
The OP is obsessing too much over autocrossing an LS7 Corvette for about 30 minutes during a 3000 mile oil change interval.
Relax.
The dry sump system in a C6 Z06 holds a lot of oil, and 1.5 minutes on an autocross course is not long enough to heat the oil to any worrisome temperature.
He could safely run the oil until the OLM says to change it. He could probably even safely use M1 5w30 instead of the 0w40.
The decrease in lead after the switch from Redline to M1 is interesting, but I haven't seen anything in this thread that changes my opinion about the cause since I posted it in 2015.
I wonder about the low Phosphorous readings that Blackstone has been getting (from 7/2016 to 8/2017), and would ask them about it. M1 0w40 should have 1000 ppm. I have noticed that Blackstone's Phosphorous readings are often less than the PDS specs, but not by that much. The Iron wear numbers were low during that period.
The Iron wear rates are all less than 1 ppm per 1000 miles, and that's pretty darn good.


Although I appreciate your input I have no idea where you are getting this "obsession over autoX" from. I used to road race regularly and don't think AutoX compares at all in terms of engine wear. The ONLY thing I was ever concerned about was LEAD level. And the ONLY reason for that was that it likely meant bearing wear. The LS7 is an extremely expensive engine to replace so I feel OCI at 3-4K and closely watching my wear metals is prudent.

And I agree about phos levels but don't see where ou get the iron wear rate calculation from??

Thanks
DH


My goodness this thread had a lot of life after I posted in it back in 2015!

But to answer your most recent question: The Iron wear rate calculation is directly from the data on the report: ppm Iron divided by the oil change interval miles.

I used to track my Camaro regularly on Redline 5w30 and never had a problem with Lead concentration in a UOA. Here is an old UOA from my Camaro on Redline 5w30: https://www.bobistheoilguy.com/foru...e-5w30-ls1-camaro-5800-miles#Post2906981
One of the big differences between your LS7 and my LS1 is that my LS1 doesn't have Titanium rods.

By saying "obsessing over autocrossing", I was trying to encourage you to extend the OCI to the point where the oil life monitor tells you to change it.

I stated long ago that the LS7 has aluminum bearings in it, and that the lead was likely coming from the connecting rod small end bushings. The LS7 has Titanium rods and needs leaded bronze small end bushings. But everybody kept saying it was bearing wear. I think it was the high concentration (500+ppm) of Moly in the Redline leaching Lead out of the rod small end bushings. So it was chemistry, not physics, that was likely causing the elevated Lead readings.


I appreciate your input and analysis.
Like I said before I am glad I took the advise of the majority here and made the switch from Reline to Mobil. I have 71K miles now and would not have wanted leaching or wearing of the lead for all this time either from street or AutoX driving. I will leave it to you experts to draw conclusions from the data I am providing.

DH
 
It was a good, positive result you got when the Mobil was switched in for the Redline. The Lead gradually decreased over the next few oil changes, and has stayed low on M1.
 
Originally Posted by bulwnkl
The lead is now being sequestered in the light varnish building up on the internals. (-; d-:


Don't say it too loud, someone could hear...
 
Originally Posted by A_Harman
It was a good, positive result you got when the Mobil was switched in for the Redline. The Lead gradually decreased over the next few oil changes, and has stayed low on M1.



Thanks, I'm very happy with the results. I will continue to post my Blackstone Reports.

DH
 
Originally Posted by bulwnkl
The lead is now being sequestered in the light varnish building up on the internals. (-; d-:


Is this a serious post of a know issue or did Rocky tell you this ???

DH
 
Originally Posted by Dirty_Howie
Originally Posted by bulwnkl
The lead is now being sequestered in the light varnish building up on the internals. (-; d-:


Is this a serious post of a know issue or did Rocky tell you this ???

DH


Rocky's one smart squirrel!

The double emoticon in my post should have tipped you off that I was mainly joking with you.

That said, the _broad generality_ of different oils showing different metal levels in a simple UOA, independent of whether actual wear rates are different, is known but not necessarily widely accepted on the internet.
 
So, you switched from the premium high-POE Red Line High-Performance 5W-30 to the lowly Mobil 1 FS 0W-40 and the high lead is gone?

Why don't you try a humble conventional 15W-40 CK-4 HDEO and see what happens. Perhaps it will take care of the high-iron issue as well.

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Thanks for posting my Blackstone here for me !!
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I'm not inclined to change the oil for the Iron where which seems stable and within normal range.
Where do you think the iron would be coming from in this aluminum block engine?

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DH
 
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