There's a diesel shop up north that I have heard good things about but have never taken my vehicle there. Of course I can't think of the name right now but they are by airport in Snohomish. Not much help here, huh?!
If you lived on the Peninsula, I'd suggest Coleman Diesel Repair in Port Angeles. Larry is a helluva nice guy and does awesome work. He's done stuff for a couple guys I know and they had nothing but good things to say. He even let me borrow his Snap-On brick to check and reset the SES light on my Dad's F250 when the Speed sensor went out. If I had a diesel, he's get my business hands down.