I'm thinking about using the larger oil filter for my 4.0L in my Cherokee. I usually run conventional 10w40 or Rotella T 5w40 with a 4,000 OCI. Mainly because the Jeep barely warms up by the time I get to school. Which filter would be better for my application, the Purolator Classic L30001 or the Motorcraft FL1A? These seem to be the best for the price.