Have been using the Mobil 301 Filter on my Wrangler 2.5L. The Mobil 301 is for the Mustang 5.0L V8, but fits 4 cyl wranglers perfectly. The 301 is about 50% larger than the regular 2.5L filter. I am able to use almost 5 quarts of synthetic fluid as a result -- basically its cheap additional oil capacity for the 2.5; about 20-25% more than stock.