I bought an oil filter at the local shop, the book didn't have 04-05 listed so I looked at the 03 WRX. Surpise, wrong size. Just venting! Sorry, that is all.

 

SubieGal, on the "other" board, claims that Subaru switched manufacturers, and that is the reason for the different model number. Of course, she also says reverse has a syncro, so I'm not sure if I would put much stock in what she says.

 

They seemed to have changed quite a bit. The oil pan is 4.2 quarts like my old RS not 4.7quarts like the 02-03 wrx. Oil filter is different and it doesn't look like purolator. And there is a #ucking plastic skid plate like cover over the bottom of my car and I had to remove to do the oil change. Not sure if I want to leave it off or put it back on.

 

Aside from the change in suppliers, Subaru decided that the smaller filter was needed to avoid a heat proximity issue with the downpipe. On newer WRXs you're supposed to use the smaller filters, on older ones either one is ok.

 

it's not the proximity to the DP, its the exhaust manifold.

 

throw that plastic peice of **** skid plate away, i did all it does is get in the way.

 

Cut a hole in it where the drain plug and oil filter is... don't worry about it again

 

The "skid plate" is actually an aerodynamic aid. I'd leave it on and follow sykosis' advice.

 

Ok I just changed my oil tonight. I bought the oil filter from a local parts store. The guy there gave me a # for an 04 model. The filter was bigger than the one on the car but I put it on. I drove the car down the street ; came back and no leaks. I did however (I know this makes no since) notice a significant loss in power. It is quite a bit warmer out tonight than it has been. Also I used mobil 1 5w-30. any thoughts?

 

You should have gone back and gotten the smaller filter. However, you can probably just wait til next change. The power loss is unrelated to the oil change, unless you over/underfilled it.