Folks, I'm looking at a 2010 S4 that happens to be out of state. The dealer (non-audi of course) doesn't know if it has the sport rear diff and doesn't have the original sticker. What's the easiest thing for these guys to look for to determine if it has it or not ?
Thanks

 

If there is Drive mode selection buttons (Comfort/Auto/Dynamic) on the centre console (between the shift stick and the cup holder), then the car is equipped with Sport Diff, may be even with Audi Drive Select if you are lucky.