Not sure if this is "automatically" done when you registered your used vehicle, but you want to make sure that YOU are notified of any recalls or Technical Service Bulletins (TSBs). These are typically corrected by your authorized MBZ dealer at no cost (regardless of the age of the car). Then again, almost all recalls/TSBs are safety-related . . . MBZ doesn't want any lawsuits. You may want to try searching the web for extended warranties, or your insurance agent may be able to help you (my Allstate agent approached me with an invitation for an extended warranty on our 1998 Chevy Astro Van). Other than that, warranty expiration means you're on your own
Hope this helps.