Hi - have had my 2008 since new and it's been great. A couple of weeks back the rear of the seat stopped moving up and down. (The front of the cushion is fine, and the seat moves forward/back)

I've done a bunch of searching and found fixes for the front/back issue, but nothing that relates to my particular problem. I pulled the seat and can see the motor turning - but no love! Before I start randomly pulling pieces off to try and self-diagnose, was just hoping for some insights. The dealer of course wants a small fortune to replace the whole seat(!) - but I know there's a nylon gear in there somewhere that's failed - any experiences with this?