i just recharged my trd cai filter today. it was a pain waiting for it to dry. it would've been nice to have a spare. but every 50,000 miles. wonder what it would cost to have this serviced at the dealership. would they wait 6-8 hrs to do it right? i measured my filter while i had it out and it's 7 1/4 x 12 1/4 outer dim. & 6 5/8 x 11 5/8 inner dim; FYI. i will look for a K&N as a spare.