Just thinking outside the box here:
I drive a dodge diesel and use Shell Rotella 15w40 oil in my truck and farm tractor.
I have read on other forms about Rotella oil having a smell.
I have never notice the smell, but it was said that the raw product can have an unpleasant odor. It does not hurt the oil, but some do not like the smell.
I have never noticed a strong odor from the oil, but it might be the case for you.
guess you could pull the dip stick out and take a sniff.
my dealer did say that shell had reduced the zinc content in shell rotella oil and that is making it smell for me.
others are changing to delo 400 as their oil still has the higher level of zinc. do not know that for sure as I have not been able to determine zinc levels by my research.
if anyone knows let me know the link: