GM Copper Issue

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Jun 10, 2002
Didn't want to completely hijack the Pilot thread in the UOA section so I'm starting a new thread.
-------------------------------------------------------------------------------- Originally posted by Jason Troxell: Spector has anyone found the source of that copper? Terry? I know he was working on the GM copper issue. I have a L67 motor now too (2001). Hope the copper isn't like that. But it has 18k so I don't know what it was like before. Do these engines knock like the V8's with the copper problem? I sure hope not. -------------------------------------------------------------------------------- Spector:This engine is really quiet and runs great. Source of copper, not sure but if the trend continues to move down to reasonable levels I will be fine with that.
Patman:If you look at the UOAs on LS1 engines with high copper, the other wear metals don't seem to suffer accordingly, so I think the copper in there is relatively harmless.
Ours runs awesome now too, just thinking about the future. Yeah I've noticed in the LS1 the other metals are good. But hasn't Terry noted that usually when the copper drops off they start to knock? I think he thought the copper was from a bearing going south. In that case would it cause other problems once that occurs? Terry, Any new developments on this issue?
One thing I wonder is; can the test be repeated on the same oil but to a different lab? Could the sample be contaminated? Maybe one should take 2 samples at time. If one proves to be questionable, send the other to another lab and see if the compare. I tell you a little story of lab tests. My employer offers health screening. A few years ago several of my co-workers all got calls telling them to see thier doctors immediate becuase the EKG showed problems. Scared the hell out of several people as it turned out the be a problem with testing equipment.
The copper issue on the newer GM modular engines has been discused before and it is definitely not a lab error or contamination.
[Off Topic!] In my day job I analyze refrigeration oils - there is one oil used in large chillers made by Carrier (Mobil DTE series) that when fresh goes after copper in the systems. The dissolved copper value in the oil sample will climb up to over 200 ppm when the oil is fresh, and will slowly drop as the oil additives are consumed. When the oil reaches the end of its service life and needs to be changed, the copper is normally less than 50 ppm. If the GM engine had a recent metallurgy change adding a copper component, the additives in the engine oils are likely similar to the DTE additives (ZDDP, phosphates, metal - alkyl compounds) and I would expect copper to be solublized in the oil. If this mechanism holds true, you may actualy be able to correlate the miles on the oil with the copper concentration and find a negative trend (higher copper in fresh oil and lower copper in oil with higher miles). At some point it may be possible the copper surface will 'passivate' or be covered over with a protective film and will not be susceptible to further copper scavenging. That may explain the lack of copper in the oil in older engines.
At first I thought they might be putting a copper based break in compound in the engines like Glock puts on its pistols but then I realized it would wash out within a change if thats what it was.
Originally posted by 3 Mad Ponchos: Mike, Have a look at the webpage, it's a definite trend. Cheers, 3MP
Maybe changing the oil too often is bad? Atl least the oil testing is giving you something to worry about, hey? I have 2 of the GM engines myself but I don't think I want to know what the oil analysis would say. 2001 GMC SLT Ext Cab 5.3L LM7 31,200 miles 2002 Trans Am WS6 5.7L LS1 8000+- Both are not due for change till 10/03. One other thing comes to mind, if there are in fact copper shards floating around in the oil. Good oil filters are an important item to consider (in future testing) and dialy use. If the filters are not doing the job, could this lead to higher levels. [ March 07, 2003, 05:00 PM: Message edited by: Mike ]
Spector went 4k on factory, then 12k, and 12k again with amsoil and all 3 had triple digit copper numbers if I recall correctly.
Mike, I'm not really worried, just curious. Since they all seem to do this, and there doesn't seem to be any short-term or long-term detrimental effect (other wear readings are normal, and these engines last a long time), it's just odd that GM is being so tight-lipped about the cause. Especially when it's so darn easy to document. Cheers, 3MP
here's something to think about. 2002 Camaro, LS1 engine. The motor has knocked on me at idle since it was new. It's what everyone calls piston slap, however mine will start doing it about 30 seconds to a minute after startup and continue to knock or tap until it is shut off. I know it's not "piston slap", it doesn't burn oil, and it runs great. It just has a audible and very annoying tap at idle. I've done oil analysis at 1000 miles on the factory oil, and again at 4k miles. Both had high copper numbers. What was interesting though was just before I changed the oil at 4k, I was running chevron 10w30 dino. When I first added it the motor knocked as usual. But I noticed after it had a few thousand miles on it (just before I changed it) that it seemed to quiet down. But I had 3k miles on the chevron 10w30 and it was time to change it. Out in came and in went mobil 0w40 synthetic, in the hopes of quieting the lifter tap, bearing knock, or whatever was making the noise at idle. The motor knocked just as loud if not louder after I put the 0w40 in. So now I figured it's not oil related. I'm close to 7k miles (since November 2002) with the 0w40 and what do you know, the few times I've driven the car these past couple weeks when the weather has breaked, the motor was quiet at idle even on startup and during warmup. I was planning on running the oil for 5k to 10k miles (15k on odometer) with an oil analysis here and there to see how the 0w40 is doing. I'm starting to get the impression that changing oil to frequently, or fresh oil, is the cause of the noise. Does that make any sense?
Hi Guys, I was looking for info on oil filters and oil when I came across this GM copper post. I have a 00' Silverado 5.3, I switched to Amsoil 0w-30 after the break-in at 5000k and use a AC-Delco UPF "Gold" filters. My first oil analysis at one year and 8000k on this oil came back with high copper levels, 231 to be exact. I blew it off as general wear. The next sample took place at 23,000k...came back high again, this time not as bad but, 154, still high. I inquired about this at the dealer as too where this copper was coming from, the only place he thought it could come from is the main bearings. I'm conserned...but not exactly sure where to go from here! Tony Gladski
Originally posted by TonyG: ... I inquired about this at the dealer as too where this copper was coming from, the only place he thought it could come from is the main bearings. I'm conserned...but not exactly sure where to go from here! Tony Gladski
Ford? Toyota? Dodge? Ken
1 FMF, I have noticed something similar with my 1987 304 V8. For 1 month following each oil change with Castrol GTX SL 20-50 dino, the engine has a loud ticking (Probabaly lifter or valve etc.) After 1 month, the noise almost goes away but not quite. I may try GTX 15 - 40 dino next. I have always thought this was due to the oil shearing down a grade in viscosity. [ March 12, 2003, 09:07 PM: Message edited by: Andrew ]
TonyG, 23,000 km is what in real distance... around 14,000 miles? I'd say you're still high but not alarmingly so. I'm still researching the cause. GM doesn't have any TSBs on it that I can find, checking other sources now... In any case it doesn't seem to cause any harm so don't sweat it. Just another GM thing. [Smile] Cheers, 3MP
3 Mad Ponchos, that's a typo on my part, it should be 8k and 23k or 8,000 miles and 23,000 miles. [Roll Eyes] Tony [ March 13, 2003, 05:25 PM: Message edited by: TonyG ]
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