Originally Posted by Sh0rtBus
Let me answer this as a former service advisor for 8 years.
Doesn't matter where you bought your vehicle. Service is completely separate from sales and to be honest- the two departments don't really get along that well anyway. Salesmen usually annoy the shit out of service advisors and parts counter persons. So there really is no leverage to be had with service just because you blight your vehicle from the same dealership unless the dealership offers some special deal like free oil changes or free car washes for life, etc.
You want to service your vehicle at the dealership service department that you trust and that you feel is giving you the best customer service. Everything else is negligible. Find an advisor you like and stick with him. Repeat service is how you gain leverage at the dealership. If the advisor sees that you're willing to spend money and do your recommended maintenance and repairs, they will be more apt to go that extra mile when you need them to. And if you like your advisor and get a survey in the mail, fill out every line as excellent, even if it could've been better service. If you burn an advisor on a survey you will lose his/her respect and they will not perform for you the way you might want/needed them to in the future.
This. I bought my '12 at a dealer close to my house, but their service hit the point where they annoyed me and I got tired of them. I switched to a dealer close to work - much more convenient and they wound up having a much better service dept. as well. I wound up buying my '14 from them through the DC group buy.
I did make the mistake of going to a different adviser once - the one I normally went to was busy and I needed to catch the shuttle to work. While he wasn't bad, he wasn't as knowledgeable as my normal guy. Lesson learned. Next time, I'll wait until I can talk to the normal guy.