Red Line Oil, Moly, & Copper

Messages
221
Location
IL
Hi all, I remember reading on a different thread about how Red Line "cleanses" extra copper from the system - I was wondering how true this actually is. I left Red Line Oil 5w30 in 2 of my cars (evo, mini) for 1 year. Usually they are flushed every few months (racing). However, after leaving them in the engine for a full year, it seems they are actually coming out with more copper. Is it correct that it isn't "true" wear? Both vehicles have been running RL 5w30 for multiple changes before this, which makes me think leaving this oil in the system does indeed corrode copper, not "pull extra" off of the bearings etc. It was mentioned that after 1 flush of this, the copper wear is supposed to go away, but I've been running it for quite some time now. Would be odd for both cars, after using a 1 year OCI, would show copper wear. If you look at the previous runs, you'll notice overall low copper. The intervals and use (1-3k miles, autocross) have been the same, but the copper wear spiked after leaving the RL5w30 in the car for 1 year. https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1511894
 
Last edited:

JAG

Messages
5,320
Location
Fredericksburg, VA
I’ve wondered about this for a long time. I have some Redline 5W-30 and am going to put it on a corroded and shiny penny, then heat it to around 220F for at least several hours. I want to see if it will remove the corrosion on the corroded penny or cause corrosion on the shiny one or simply dissolve copper. This test with virgin oil is far from ideal. Ideally, your used oil would be tested since it has been through the ringer in your engines. If the virgin oil test shows activity toward the copper, we may be onto something. If it does not, we still cannot conclude that Redline does not show activity toward copper when used in an engine during reasonable oil change intervals. If you could do a test with your used oil, that could give us a much better test and answer. I have done this test with virgin oils but at much higher temperatures, like 250 F to 420F. Some oils were much more corrosive to copper than others.
 

kyoo

Thread starter
Messages
221
Location
IL
was gonna say that too; appreciate the thought and two things: 1) pure copper may be better 2) it didn't show up in frequent changes, only when it sat in red line for an extended period of time
 
Last edited:

JAG

Messages
5,320
Location
Fredericksburg, VA
Originally Posted By: 4WD
1982 or older for copper? = and “shiney” …
Old and new pennies are copper on the outside. That’s what matters for the test. The cores of ones made since 1982 are zinc.
Originally Posted By: kyoo
was gonna say that too; appreciate the thought and two things: 1) pure copper may be better 2) it didn't show up in frequent changes, only when it sat in red line for an extended period of time
The second point is why it is much better if you do the test on your used oil, rather than I do it on virgin oil.
 
Messages
8,048
Location
Michigan
Copper-based bearings are made from leaded bronze, and have a lead-tin overlay. Lead and tin don't appear in either of the oil analysis reports. Maybe the copper is from a brazed oil cooler?
 

kyoo

Thread starter
Messages
221
Location
IL
Originally Posted By: JAG
Originally Posted By: 4WD
1982 or older for copper? = and “shiney” …
Old and new pennies are copper on the outside. That’s what matters for the test. The cores of ones made since 1982 are zinc.
Originally Posted By: kyoo
was gonna say that too; appreciate the thought and two things: 1) pure copper may be better 2) it didn't show up in frequent changes, only when it sat in red line for an extended period of time
The second point is why it is much better if you do the test on your used oil, rather than I do it on virgin oil.
It's testing two different ideas - one is that RL gets more corrosive after use/time, and two, that long periods of time bathed in RL corrodes copper. It would test the first idea, but not the second. I did a TBN on one of them and it looked fine.
Originally Posted By: A_Harman
Copper-based bearings are made from leaded bronze, and have a lead-tin overlay. Lead and tin don't appear in either of the oil analysis reports. Maybe the copper is from a brazed oil cooler?
I'm not sure where the copper is coming from, but no changes were made to either car over the year the oil sat in it.
 
Last edited:

MolaKule

Staff member
Messages
21,838
Location
Iowegia - USA
Originally Posted By: JAG
The second point is why it is much better if you do the test on your used oil, rather than I do it on virgin oil.
To know exactly what the installed oil looks like helps greatly with a UOA analysis.
 
Messages
10,004
Location
Waco, TX
Originally Posted By: A_Harman
Copper-based bearings are made from leaded bronze, and have a lead-tin overlay. Lead and tin don't appear in either of the oil analysis reports.
Agree - usually once you are “down to the copper” the bearings are DONE!!!
 

kyoo

Thread starter
Messages
221
Location
IL
thanks, unlikely that the bearings in both cars failed, so probably pulling copper from something else.
 

kyoo

Thread starter
Messages
221
Location
IL
yes - oil cooler has had no change during the time, but certainly does. actually i'm assuming all modern cars did, i'm not sure about the mini (second UOA). the evo (first UOA) does.
 
Last edited:

JAG

Messages
5,320
Location
Fredericksburg, VA
I would guess it’s all or mostly from the oil cooler. I dug up some good, old threads on this subject. See below. After seeing them, it jogged my memory. I think the case is strong that Redline’s MoDTC can corrode copper, in some conditions. I also read a patent that pointed out the potential tendency. There are additives that may be part of the additive package that passivate the copper to lessen corrosion, but they aren’t perfect and they can degrade with use. I would not stop using Redline based on this. Your copper levels are not very high. It is a great oil but there may be better oils in your application. https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1336508 Be sure to check out this link, which is also in the above thread: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1278421&fpart=2
 
Top