JK Replacement Part List is your local resource for alternate parts!
I use a Ryco Z37 or equivalent other brand for oil filter, same diameter & fitting, but twice as high, so
should last better. lately I have been using the
Penrite HPR diesel 5 in the 3.8, since I can get a 10L for ~$80 from Repco & get a change for both the car and the bike out of it.
It also means I don't run the risk of running out of oil in the engine if I leave it a bit long between changes. The recommended oil seems to vanish into thin air, so that the level has dropped below the low mark between changes. Compared to the bike, the previous TJ & the Corolla before it that never used a noticable amount...