The most difficult part is getting the coils out. Once the coils are pulled and let to hang out of the way, it's easy. To get to that point, the battery is moved out of the way on one side, the air filter box on the other.

The spark plugs are pricey.

 

Dealerships are charging somewhere around $140/hr for labor. I would do it myself, or bring it to an independent shop for plug replacement.

 

Yeah, depends on location, but that's probably not an unusually high dealer charge. A good mechanic should be able to get it done with Denso plugs for well under $300. A popular local shop recently quoted me $320 for my 6 cylinder and I'd say service is moderately overpriced in my area.

You can find plenty of DIY videos on YouTube, along with the entire spectrum of feedback from members (anywhere from simple to a complete PITA). I get them impression that the job gets much easier with the combination of having the right tools, technique, and good dexterity in tight spaces.

 

I paid $272 for mine, but the dealership was also doing a compression test so I may have gotten a slight price break.

 

My 3.6 cost less than that at my dealer.

 

That’s a bit high but not outrageous. You can buy the plugs on your own and use a discount code from one of the chain parts stores and use an Indy shop that lets you bring parts an get the cost down but it will save you maybe 100 or so dollars depending on where your at.

 

Find a local repair shop, don't pay the stealership for this job. There is nothing special that the dealership needs to do.

There are also How to's on line to walk you through DIY. Also post on this forum and most Subaru forums.

I leave the wires on the coils when I change my plugs. Because the plastic clips can break, there is a black ziptie around my #3 coil. It's been there since 2008.