As I understand from this and other sites, the '08 job 1's had the external filter. The job 2's and 3's had an improved internal pan filter that negated the need for the external jobby. As I remember, only 10% of the fluid went through the external (and to the cooler), while 100% goes through the pan type.
Because you don't have the external, I'm guessing you have the improved in-pan type filter.
Tim