Are you sure the Mobil 1 filter for the Infiniti FX45 is an M1-109? Everything I see shows it being the M1-110 for the 2003 - 2008 models.
The M1-110 cross-refs to the Wix 51356 with the following specs:
- Height = 3.402
- OD = 2.685
- Thread Size = 20X1.5 MM
The M1-109 cross-refs to the Wix 51311 with the following specs:
- Height = 3.372
- OD = 3.661
- Thread Size = 3/4-16
The OD of the two are quite different, not to mention different thread sizes.