My heart sank when I saw it. No misfires at all, so I would have never known had I not changed the spark plugs. It's only in one spark plug tube, the front passenger side which is cylinder one. I didn't have the time to replace the valve cover gasket along with tube gaskets so this will be a future task. It doesn't look like a big job, just something I've never done before. When looking at the spark plugs pic, it's the last plug all the way to the right. Any tips would be appreciated. Thanks.
I changed the spark plugs on my 2015 Subaru Crosstrek and found oil in one spark plug tube
- Thread starter Jeep_Riot
- Start date
How many miles on the car and plugs?
118K total miles and the plugs have about 60K miles on them.
The spark plug tube seals/valve cover gasket job is often impossible on most Subarus due to not having enough room between the frame and the engine 
If you want to replace them, get the Mahle set on Rock Auto. The tube seals are included with the valve cover gaskets.
It might be worth using stop leak and see if it leaks less
If you want to replace them, get the Mahle set on Rock Auto. The tube seals are included with the valve cover gaskets.
It might be worth using stop leak and see if it leaks less
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I put the new plugs in. Before I did I cleaned the tubes really well with brake clean to make sure there were no traces of oil.
The million dollar question on my mind is how long has this been going on? No way to know, I guess.
I’ve always tried to use OEM parts on this Subaru. Are aftermarket gaskets known to be good-to-go?
Yeah you can use OEM with no problem, though most people don't want to spend the money on OE.
The Mahle gaskets are made in Japan and probably from the OE supplier.
If you want to buy yourself some time before replacing the gasket, I've found that something like Permatex Ultra Black applied around the seam will stop the seepage until you have time to do the job…or longer, LOL.
Just need to clean the area, and allow it time to cure.
Just need to clean the area, and allow it time to cure.
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- Jul 18, 2022
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2nd this, keep an eye on it. Change when convenient.
It is tight, but not impossible. An H6 Outback is way tighter that that!
It is tight, but not impossible. An H6 Outback is way tighter that that!
Nah, I’ll pass on any of those stop leak products.It might be worth using stop leak and see if it leaks less
I did switch over to 5w-30 High Mileage from 0w-20 after replacing the plugs, so hopefully that’ll help some. Also replaced the PCV and hose.
You think?
Fantastic engine though and comes with 5EAT and the VTD drive system. Has 6-1/2 quarts of oil and standard fluid/oil cooler.The only outward difference on most of the Gen 3’s (2005-2009) was a 3.0R badge. We remove it….
JTK
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I took the splash shield off last weekend to do the coolant change and took a good look around everything from under the car. This is in fact the only seepage I could find (in the process of changing the plugs). I doubt I could leave it as is, though.
I like keeping my car in the best possible condition, and I like doing so myself to save money. Only the good Lord knows how much I love saving money.
How does this help the tube seals?
I mainly only use OE if the part is updated. Why would you want OE, that is literally the part that is broken...
makes no sense.Try High milage thicker oil?
