Mobil 1 5W30 getting dark so fast?

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Cool running makes sludge, so your hot running is good. It may be graphite or assembly lube. There is always some oil left after a change, and graphite or such will continue to pollute your oil. Sounds like you're doing the best things possible, especially draining the factory fill early and using a good filter. Getting dark means it is holding things in suspension, should be good. With hard driving your rings/cylinder walls should have been well fitted together by now. It should take only a couple hundred miles of correct break in to get to a stable ring/wall condition.
 
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Originally Posted By: Danh
Assembly lubes are used abundantly,in new engines and they are typically rich in molybdenum. When the engines are run the assembly lubes mix with the engine oil, turning it dark and glittery almost immediately. This is almost certainly what you saw with the drain of the factory fill. And as there is always a good amount of residual oil in an engine even when drained, this is likely what you are seeing in the fresh Mobil1, too. So, nothing to worry about.
+1 for leftover residual moly that turns the oil dark very quickly.
 
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Originally Posted By: Danh
Assembly lubes are used abundantly,in new engines and they are typically rich in molybdenum. When the engines are run the assembly lubes mix with the engine oil, turning it dark and glittery almost immediately. This is almost certainly what you saw with the drain of the factory fill. And as there is always a good amount of residual oil in an engine even when drained, this is likely what you are seeing in the fresh Mobil1, too. So, nothing to worry about.
This is the true story. Copper, moly, etc. are all used, and typically beneficial to the engine during break in, which is virtually a non issue for most modern cars today.. I have had fleet trucks shedding copper at 100k miles, yet the engine went to an honest 200-300k miles before rebuild.
 
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I agree that it's nothing to worry about, but I'm not sure I assign it to any assembly lube, though that may be true. I had a 2011 Camry that I bought new and I swear the factory fill just wouldn't change color. It was changed at 5k miles and was still a golden amber. Same at the 10k mile mark. On the other hand, our 2005 Acura, with over 110k miles on a very fully broken-in engine, significantly darkens any oil after just a few thousand miles. Our 2008 Honda, with close to 100k miles, is about in-between...the oil's certainly turning color by 5k miles, but it's not real dark yet. Different engines just tend to color different oils...differently. Some people report different rates of color change in the same engine with different oil. If you're curious, you could switch brands once to see if a different brand behaves differently. Either way, I don't think it's something to worry about.
 
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My experience with new cars, and that's what we are talking about here, is that they don't darken oil quickly.
 

pbm

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[quote=GM4LIFE]pbm, What oil filter are you running? I've been running the AC PF2257G which appears to be made by Hengst.
 
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