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2007 Subaru Impreza Oil Residue

I was changing my oil yesterday and noticed a significant amount of oil residue on a bracket located approximately at the center of the front axle, to the left of the oil pan. I’m confident the leak isn’t coming from the oil pan, drain plug, or oil filter, based solely on the location of the buildup, but I was not able to see specifically where the build originated. As this is a Boxer engine, my concern is that the underside of one of the head gaskets may be leaking. My only reservation about this theory, however, is that I haven’t smelled any burning oil or witnessed any grey smoke.

Unfortunately, I haven’t paid close attention to the oil levels in recent moths, so I can’t say definitively whether or not the levels have fallen since the last oil change.

Can anyone lend some insight as to where the residue is coming from and if it’s a problem requiring immediate attention?

How many miles does this puppy have on it?

Without seeing the engine I can’t lend any specific insight, however:

Oil seepage through a gasket with some years on it is common and, not the same as a blown headgasket (which would be from the compression chamber to the water jacket and might or might not involve an oil channel). And the gasket may be the oil pan gasket.

The second most common source of oil under the engine is probably a main oil seal or cam seal. Again, not serious as long as it isn;t soaking a timing belt.

Neither of these will cause gray smoke (burning oil), as neither lets the oil into the coombustion chamber.

Yours may not even be oil. It may be tranny or transfer case seepage, again past a long-compressed gasket.

None of these leaks is serious PROVIDED you keep the fluid levels up. However, if you are having seepage from the transfer case gasket, it might not be a bad idea to get it changed.

I really appreciate the insight and oil from the transfer case was my next thought.

The car has about 75,500 miles on it and many different pieces are beginning to wear out, including the belt tensioner and rear diff(this one I’m THRILLED about).

I hope to get back under the car this weekend and post a couple of pictures to show exactly where the problem lies.

The most common source of oil seepage on these engines is from valve cover gaskets. Before engaging in anything more involved, I suggest that you retorque the bolts holding the valve covers. More than likely, this will resolve the issue.

Really track down the source of the leak first before doing anything! Where you see the oil drip is probably not the source

Find out what your oil use is. Sounds like you dont really know how long this has been an issue. You also could drop 7 bucks at a car wash to carefully clean the buildup areas and keep an eye on the new build up.

I spent a small bucket of money to replace suspension bushings (control arm bushings I think) which the alignment specialist told me were damaged by oil leaking from a crank seal. That wasn’t a Subie, but I presume you have rubber parts in jeopardy.