Cloudy oil?

Pulled the oil filter after 300 miles on Driven dt-40 after changing from Mobil 1 0w40. I had my headlamp on and when I shined it down the filter housing, it looked muddy. Took an oil sample and poured the excess in a glass beaker. Running down the beaker it looks like regular oil. Let it settle over a couple days and there’s no separation. When I hold it up to light from the bottom, looks totally normal. I’ll attach some pictures to show what looks a little alarming to me. It could just be a light trick, but wanted to see if anyone had a similar experience. Could be from residual 0w40 mixing with the new dt40? Seemed off to me though.

The pea soup colored oil is not normal and looks like oil that has been frothed up with a lot of moisture or possibly coolant. What's odd to me is that you're saying it didn't come out looking like that to begin with? Any water contaminated oil I have even seen looks like that right from the beginning? Had the car been driven up to temp before the oil change so that any moisture in had evaporated off? This is why short trips where a car never get the oil hot enough is a bad thing since the moisture doesnt get burned off, but Im not so sure at this point on your car since the oil came out looking normal in the first pic you have posted. The second and last pic doesnt look normal at all unless its a lighting illusion

Hey @mkemp590 - Thanks for posting. What P-car did you drain this off of? I honestly don't like the color of that; my gut says that there's moisture getting into your oil. I just did a quick online search which confirms this: " Motor oil turns milky brown when its been contaminated by water . Most vehicle coolant systems use a blend of water and antifreeze - and if the coolant system is allowed to leach into the engine oil, that tells us that an engine gasket has failed." Sorry if this is potentially bad and costly news. What would I personally do? I would immediately drain the oil out of the car absolutely as much as you can (jacked up flat)...and refill with the original Mobil 1 plus a new filter...and then start from there. Also save what you have there for a mechanic to check out. New synthetic should not look like that. Is there any chance you may have overfilled your oil? If so, I think that can blow seals. Granted, another oil change (even DIY) is more money spent, but you want a baseline to see if there is a much more important problem going on here (like the aforementioned coolant getting into your oil) that could be a much more expensive repair. Meanwhile, your engine is likely not being protected and you don't want to accidentally kill it. Just my two cents and cheering you on here.

Hey! Thanks for the reply’s! So that’s all the same oil. All from the filter housing. First picture and third picture are in ambient lighting. Second and last are with my bright head lamp pointed at it. It’s a 08 Cayman S . It’s been sitting for about a month and a half and hasn’t been started. I meant to check the oil after the last time I drove it before it got too cold but never got around to it. The last time it was started was just to move it around in my garage last month. I know it’s not good to only run it for a few minutes, so it’s just been sitting on a battery tender until the weather gets nicer. I changed my oil to dt-40 after my last oil change was with Mobil 1 0w40. I didn’t know better at the time and thought I would use the factory recommended oil. On my first oil change on that oil, I saw glitter and small black plastic bits in the filter. No oil burning, no smoking, scoped from sump and no deep scratches from bore scoring. Put in the new oil, and only got to run it for about 300 miles before the weather turned. I was curious and wanted to check the filter and see if anything else showed up in it. Filter looked good, just the odd color of the oil in the light. Also, the oil that came out before this got an analysis and wasn’t contaminated.

I’d be on the phone or emailing with Driven ASAP. I’m sure they will want a sample. Perhaps send one to Blackstone also. Seems like you knew something was awry if you are checking the filter at 300 miles [emoji1745]. Shawn in VA (USA)

I had that color of oil in my Exige after my alternator crapped out and wasn’t getting any spark and all that fuel not being burned off… not saying that’s not moisture either… but that’s how mine looked. I drained it, replaced the alternator and it never did that again. For some reason my battery took me waaaaay further than a Lotus battery should have before I died… like 100 miles plus… that alone was mind boggling since the battery is the size of a cell phone 🤷‍♂️

I'm guessing LED headlamp? Try a bright incandescent light, or try the LED headlamp on a fresh oil sample for comparison. "White" LEDs have a very different spectrum than traditional bulbs: they tend to put out a lot of blue and near-UV, and I've noticed they can make oil kind of glow. Looks similar to what you're seeing. If it looks fine with a bright regular light or the LED makes a fresh oil sample look similar to that then it's something in the oil glowing with the LED light rather than a contamination issue.

Send a sample to Blackstone

I agree with the others here. Milky usually means water/coolant... that last picture is very bad looking indeed. Next step is to send out a sample - if it's coolant, you'll see coolant elements in the sample clear as day, so it will be obvious after the analysis. Fortunately the car is parked still, otherwise I'd say you should call Blackstone (or whoever you want to use) to ask for any rush processing... but I wouldn't drive or run the engine if you can avoid it... that's how bad that sample looks. As for next steps... you may consider running the engine and seeing if you get any bubbling from the cooling system. I don't even know if you can do that on these cars. Historically, when I've seen this type of situation, you check at the radiator cap to see bubbles there - that can mean the compression from the cylinder is pushing into the cooling system (past the head gasket). At the same time, you can see if there is any contamination there. I don't know if that's possible in these cars... but it's worth a shot to look. I'd start there. I feel panicked for your sake... I apologize if I'm scaring you!

I wonder if you tossed a match on that mixture. If it’s water probably won’t light?

Can't see the logic in testing that mixture with flame. I would inspect the head gaskets, if they are leaking there should be evidence at the heads too.

It was just a “what if” there are plenty of things you can check

Sure, and I'm not trying to denigrate your suggestion I just believe flames and vehicle repairs are a bad mix. I saw a 70' vette engine go up in flames from a fuel leak. It was inside the Exxon. Had it spread and not been extinguished there was plenty of other fluids at that site to ignite.

I meant take a little amount into a glass jar and see what happens… but scratch that idea because when I had fuel in oil I tried it and would not light… when I did that I wasn’t sure what it was either… mine was the same green/brown color. Knowing the alternator was out I figured it was gas… very strange scenario tho.

Flame testing may tell you if you have fuel in there, but it's not going to tell you much of anything else. Most likely, it won't flame up anyway - most oils don't flame up like that. Heck, even gasoline won't flame up unless it's at the correct concentration (Mythbusters did some testing on this). Most oils, like diesel fuel, which is actually an oil, won't light at all in that manner, because the air/fuel ratio isn't correct. Bottom line, I don't see a point to testing with a match at all.

I tried it, it doesn’t flame up

As others have recommended, I'd do an oil change and send a sample for analysis (leaving the car parked until receiving the results). That said, I will not be surprised to learn that you (and @gubi ) are onto something about the LED light playing tricks.

Just curious, is the coolant level on par? How was the car idling/performing? If it’s a HG issue these are some things that would wear it’s ugly head.. This was a while ago and I forgot but in my RX-7 I had an injector stick open and the oil looked like this too… just another idea for to look at… i think that is fuel, of course cylinder walls and rings don’t like raw fuel… Do a search. Just trying to help

Just an update. So I did a few comparisons between brand new oil, the oil I removed, used oil, and new and used oil mixed with water. The new oil gave somewhat of a muddy color where the led lamp hit it, but not nearly as opaque as the used sample. The current used sample looked exactly the same under led light as the old used sample. All of the samples were completely transparent when held up to a light source and transparent on the sides of the beaker. What I also found was that samples with water added were not transparent at all and had a much higher viscosity. After awhile, they would also start to separate. To me, it seems like there isn’t really a contamination issue but rather a worrying optical illusion ha. What do you guys think?

Looks similar?

The fact that it only looks like that with the LED light and not in normal ambient light makes me think this is now just an illusion. Contaminated oil will look wonky in normal light just like the image that Porsche08 posted above. If its bad, it should be bad all the time and not just with one specific light source.

Not a bad idea. There was a very small amount of fuel dilution in the last oil analysis. I didn’t have any gas around to compare fuel mixed in the oil. I know leaky injectors facilitate bore scoring in these cars. I guess I’ll send out the sample and find out! Good news is that I have another 3.4 with bore scoring I bought to resleve and build out. It only had 40k miles on it so I’m thinking about swapping out the injectors, water pump, and chain tensioners. My engine has about 80k on it currently.

Immediately check the coolant reservoir to see if the coolant has been contaminated with oil. If it has, do not start the engine, have it flatbed towed to someone who can pull the engine, check gaskets, etc.

this is such a strange thread. Don't you have lights in your garage ceiling? can't you just see what the color of the oil is by looking at it? why do you have to shine a light into it? that milky oil looks like obvious coolant contamination to me. to bring this screwy thread back into engineering alignment, you need to drain all of the oil, replace the filter, fill it back up, and then run the engine for a while I don't know maybe 20 minutes. If it's not making any strange sounds and if no white smoke is coming out of the exhaust, then run it longer. after it cools off, let out a little bit of oil from the drain plug into a beaker and check it out. you don't have to drain all of the oil.

Did you get your Driven Oil from L&N Engineering? Call Charles Navarro at L&N. [phone removed]

You could settle this for good in a matter of minutes by pouring some fresh oil in the same glass in the images and shine the same LED light into it. It clearly cant be contaminated with anything if it looks the same as your drain sample did

Keep in mind that Driven has a higher percentage of additives in its oil than other brands so what you may be seeing is the particulate dispersed in the oil resulting in a hazy appearance.

I’ve used joe Gibbs oil (driven) and never saw that color I’m friends with a nascar chassis builder, I’ll see what he thinks that is. There’s nothing that guy hasn’t seen

Here’s another unknown oil sample from the engine I’m breaking down. Looks almost identical. I think it’s a light issue. New oil doesn’t quite look like this when the same light is shined on it, but used oil does.

That’s new oil? As in you emptied out that old chit and put new in?

An old trick I used to check for suspected water in the oil was to drip some oil off of the dipstick on to the hot exhaust manifold and if it smoked it was oil, if it sizzled (even a little) it had coolant in it. Unfortunately we have no dipstick or access to the exhaust manifold🤔. If you have another vehicle with a front engine you may still be able to test your cloudy oil if the moisture has not already evaporated??? Jim