Just as an added piece of info (that probably has been mentioned before) for anybody like me that only uses K&N Oil Filters:
I just talked to Champion Labs, who make the K&N and Mobil 1 (and the Royal Purple) and the only difference in the two is the "Wrench Off" nut (that I have never used) on the bottom of the K&N.
don't forget another quart to make 7, 6.5 quarts for ours...
HEADS UP, went at lunch and had to buy the individual quarts, not a 4 and a spare... I actually thought it was a 5qt like others but Mobil1 puts theirs in a gallon jug. :dunno: Anyway, picked up two sets, but one of the filters fits my dad's (I got the last M1 for TBSS.)