I had something unusual happen with the last oil change on my 97 Nissan PU (2.4l 4 cyl, 188k miles). The engine runs normally, no unusual noises, smooth as ever, no oil consumption, no oil light, but the oil light does come on with the engine not running, i.e. just before starting the engine. Wednesday, I am doing an oil change and all is normal until I remove the oil filter.
This filter is a real bear to remove, it can only be done with a cap wrench, two separate extensions (6" and 3", in that order) and ratchet. Normally, it is very tight, but this time, it wasn’t even finger tight, it just started spinning off. I had been running the engine so it was warm as I always do for an oil change. The second unusual thing was that usually there is a lot of oil spilling out of it as I remove it, this time nothing. When I got it off, it was bone dry. It had oil in it at one time but it looked like it hadn’t had any in awhile. The drain back seal was dry like it hadn’t seen oil in months and the oil filter gasket was dry as well.
I finished the oil change, I’ve driven the truck for two days now and it still runs fine. Go figure. BTW, the oil stays pretty clean in this engine. It just gets a medium brown, never black. That is true of all of my vehicles though.