The oil filter is on the bottom side directly in front of the oil pan. You can not see the filter because of the deflector. They put a nice circular hole in the deflector so that you can access the filter but it is about four inches off which makes it almost impossible to access. The easiest thing to do is remove the front bolts so that you have better access to it.
2008 Mazda3 take 4 qtz of oil
Check out http://robert.aitchison.org/tiki-page.php?pageName=Mazda3+DIY+Oil+Change
The 2008 Mazda MAZDA3 has 16 valves.
The 2008 Mazda MAZDA3 is a gas-powered vehicle.
The 2008 Mazda MAZDA3 has a 5-speed manual.
The 2008 Mazda MAZDA3 has an inline 4 engine.
The height of the 2008 Mazda MAZDA3 is 4 ft. 9.7 in. (57.7 in.).
The 2008 Mazda MAZDA3 runs on regular unleaded.
The 2008 Mazda MAZDA3 is 14 ft. 9.4 in. (177.4 in.) long.
The 2008 Mazda MAZDA3 has a drag coefficient of 0.29 Cd.
The 2008 Mazda MAZDA3 has double overhead cam (DOHC).
The curb weight of the 2008 Mazda MAZDA3 is 2780 lbs..