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?
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?