2017 2.7L EcoBoost with 115k miles. Bought it at 35k and have changed the oil religiously every 3k miles with Mobil 1 Full Synthetic.
Today, I did an oil change and noticed something weird—there’s a muddy-looking oil in the catch can. But when I drained the oil from the truck, it looked totally normal. The color difference between what’s in the catch can and what came out of the pan is huge.
I attached a photo showing the difference.
Any idea what’s going on? Should I be concerned?
That’s just PCV vapors condensing in the catch can. It’s a mix of oil, fuel vapors, and water—totally normal, especially in cold weather. Just make sure to empty it regularly so it doesn’t get sucked back in.
@Hart
Well, oil is already part of ‘hydrocarbons.’
Aspen said:
@Hart
Well, oil is already part of ‘hydrocarbons.’
Yeah, basically it’s just hydrocarbons and water separating out.
Can’t edit my post, but I just wanted to say thanks to everyone. Y’all are awesome. I was freaking out, but it makes sense now. It’s been crazy cold here in Dallas, and that’s probably why I’m seeing this for the first time.
Totally normal.
It’s just condensation. Happens a lot if you do short trips in colder weather.
I just changed my oil today and saw the same thing. Nothing to worry about.
Happens all the time, normal.
The forbidden coffee. 
Most likely condensation buildup inside the catch can itself.
1000% normal, especially in winter. The cold makes it mix with water and some fuel vapors.
Unless you see signs of coolant in the oil or metal shavings, don’t stress over the color or consistency. Just be glad that junk isn’t getting dumped back into your intake.
@Luca
Are catch cans factory-installed? If so, where would I find it on a ‘19 3.5 EcoBoost?
Hollis said:
@Luca
Are catch cans factory-installed? If so, where would I find it on a ‘19 3.5 EcoBoost?
Nope, they’re aftermarket. If you want one, they’re easy to install and not too expensive. I’m using a JLT 3.0 on mine.
I have one. Here’s the website where you can find them—just enter your truck info. Great company, super helpful staff.
Any chance it’s a blown head gasket? Coolant in the oil can look like that.
I see the same thing all winter. Once summer hits, it clears up.
Wait… I have 500k miles and never even knew I was supposed to be draining something? Where is this catch can? I swear there’s nothing in the manual about this!
