Can a GDI engine blacken oil in just 25 miles? (See pics)

The VQ35DD in my 2019 Nissan Pathfinder blackened the oil very quickly, but I'm not sure it was quite that black in 25mi. OTOH, the VQ38DD in my 2022 Frontier takes much longer, as do the other GDI engines in my family fleet.

I'd want to change the oil again just for comparison.
 
That's what I was thinking maybe they didn't get all of the old oil out and then it mixed with the new oil. Has the filter been replaced?
 
The drain plug and filter are under a swing-down shield so I can't see or get to them to mark without a lot of work, plus it's 28° here. After bringing this to their attention I'm sure they will change it this time. The oil on the dipstick before the oil change was dark, as was the sample from the last oil change, but they were after 5,000 miles. I doubt that a quart of residual oil would have darkened the 5.4 quart sump that much, but who knows.

I believe this is a reputable dealer. I have been using them for six years and have been very satisfied with their work. The place is clean as a whistle, has eight lifts, and a large window where one can observe their work. I was too busy watching my wife drool over the 2025 yellow twin turbo Z on the floor to pay attention to what they were doing. Not sure what went wrong here, but I'll have them change the oil again tomorrow, will watch through the window, and pull another sample when I get home.
 
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I’ve got 3 of those engines, one is an 18 so it not GDI, but my 21 and 24 are. Neither has ever done anything like that in 2500, let alone 25 miles. I’d go straight back to the dealer.
 
I had a 2016 Hyundai DI engine. It blew soot out the tailpipe like crazy but never darkened oil that quickly.
 
I get free oil changes from my dealer for my 2019 Altima, which has a PR25DD GDI engine. After getting the oil changed yesterday, I drove 25 miles home and checked the dipstick. To my surprise the oil appeared black, so I pumped some out through the dipstick pipe and it is super dark, looks black in the bottle but very deep red in thin film, sort of like Coca Cola. I pulled two more 8 ounce samples just to be sure everything was flushed and it is just as dark. Even with a bright flashlight behind my sample, no light is visible through it.

I called the dealer and asked them to check with the mechanic who did the oil change to see if he may have forgotten to change the oil as I had other work done as well. The mechanic distinctly remembered changing the oil and filter, so I asked them to check their bulk tank. They sent me a photo of a sample from the bulk tank and it is golden. The dealer offered to change the oil again, which I plan to do.

The oil is a 0W-20 which they tell me is a full synthetic from Mobil, although the paperwork shows it as Nissan Genuine Oil (could be both). I did an 5,000 mile UOA on the last change at 50,000 miles, and while about 10% lighter than expected in additives and viscosity, it was still reasonably consistent with API SPs oils and the wear metals were excellent.

I know GDI engines generate some soot, but is it possible for a GDI engine to blacken the oil this much in just 25 miles of highway driving?

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How did it smell? Should be different than brand new oil. And it sounds like they didn’t change.
 
The drain plug and filter are under a swing-down shield so I can't see or get to them to mark without a lot of work, plus it's 28° here. After bringing this to their attention I'm sure they will change it this time. The oil on the dipstick before the oil change was dark, as was the sample from the last oil change, but they were after 5,000 miles. I doubt that a quart of residual oil would have darkened the 5.4 quart sump that much, but who knows.

I believe this is a reputable dealer. I have been using them for six years and have been very satisfied with their work. The place is clean as a whistle, has eight lifts, and a large window where one can observe their work. I was too busy watching my wife drool over the 2025 yellow twin turbo Z on the floor to pay attention to what they were doing. Not sure what went wrong here, but I'll have them change the oil again tomorrow, will watch through the window, and pull another sample when I get home.
I would guess honest mistake. Communication within dealerships is not so good.
 
I get free oil changes from my dealer for my 2019 Altima, which has a PR25DD GDI engine. After getting the oil changed yesterday, I drove 25 miles home and checked the dipstick. To my surprise the oil appeared black, so I pumped some out through the dipstick pipe and it is super dark, looks black in the bottle but very deep red in thin film, sort of like Coca Cola. I pulled two more 8 ounce samples just to be sure everything was flushed and it is just as dark. Even with a bright flashlight behind my sample, no light is visible through it.

I called the dealer and asked them to check with the mechanic who did the oil change to see if he may have forgotten to change the oil as I had other work done as well. The mechanic distinctly remembered changing the oil and filter, so I asked them to check their bulk tank. They sent me a photo of a sample from the bulk tank and it is golden. The dealer offered to change the oil again, which I plan to do.

The oil is a 0W-20 which they tell me is a full synthetic from Mobil, although the paperwork shows it as Nissan Genuine Oil (could be both). I did an 5,000 mile UOA on the last change at 50,000 miles, and while about 10% lighter than expected in additives and viscosity, it was still reasonably consistent with API SPs oils and the wear metals were excellent.

I know GDI engines generate some soot, but is it possible for a GDI engine to blacken the oil this much in just 25 miles of highway driving?

View attachment 258976 View attachment 258978
The oil was never changed.
 
this is one of the reasons i still change my own oil. its a numbers game. most folks that take it to a dealer for oil change don't look at the oil with the exceptions of bitog folks . kinda like timing belts . they charge for 10 and only really do 2 of them . they give you a 12 month 12k mile warranty . How many do you think will break in that 12k miles?

the only experience like this was when my mother took her honda to get oil changed. they charged her oil and filter. the next oil change i found the same filter from the previous oil change before that was still on there. i know because it was not a honda oem filter
 
this is one of the reasons i still change my own oil. its a numbers game. most folks that take it to a dealer for oil change don't look at the oil with the exceptions of bitog folks . kinda like timing belts . they charge for 10 and only really do 2 of them . they give you a 12 month 12k mile warranty . How many do you think will break in that 12k miles?

the only experience like this was when my mother took her honda to get oil changed. they charged her oil and filter. the next oil change i found the same filter from the previous oil change before that was still on there. i know because it was not a honda oem filter
Same reason my grandfather in his 80s was crawling underneath his truck. God willing and the creek don’t rise and I’ll be doing the same. I don’t like taking my cars in for recalls. I don’t want strangers touching my cars.
 
Exactly so. Some engines in cars (including pickups) will hold as much as a quart in the pan plus elsewhere, making it impossible to ever get an oil change that looks new barring just dumping a few gallons straight through from filler to open drain bolt (and maybe not even then).
I've done more oil changes than I can count in over 50 years and realize there is residual oil remaining, up to a quart maybe a little more depending on the vehicle and how long the tech allows the oil to drain. I have never seen oil looking that dirty in a gas powered engine even after driving way, way longer than the OP did in a well maintained vehicle. In fact in any of my vehicles that oil looks like it went a full OCI. I'd be willing to bet the OPs vehicle is well maintained, and that oil wasn't changed, GDI or not. If it were a diesel engine I'd think otherwise.

Now if the tech did change the oil, maybe he left the filter and half the sump capacity, in which case he should get the boot for not doing the job right. IMO the smart money is on the oil wasn't changed.
 
Ouch! Probably happens way more frequently than it should. Hopefully just a one off mistake for you moving forward.

I do like VIOC and Take5 who show you the dip stick being clean and full right before you leave. You never get out of the car so you know it was your clean oil. Also the invoices do not match up from what I have seen pretty often too and mostly with the oil filters. Would not shock me if it was same with the bulk oil. Though I have seen the VL branded truck filling the bulk tank at VIOC. Surprisingly I have gotten better than what was on the invoice many times with oil filters. Like an STP XL when a PZ or VL branded jobber filter was cited. Surely I’ll take that “mistake.”
 
Free spelled backward is EERF. And that the sound your engine will make when using free changes. Have seen this many many times. We have to babby sit these people unfortunatly... Used motor oil or never replaced for sure. Go back and have them replace it. next time sample the dipstick oil on a paper towel before going in. Sample again afterwards perhaps. Sad to hear!
 
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