Just joined up here but that doesn't mean I haven't been reading here fixes and great advice from how to change lights to snow tires for the past two plus years.
We have a 2003 E320 bought new and basically it's treated us kindly with 69,000 miles presently. Most of the main issues were covered during the warranty time frame ie:
* Water Pump went @ 9,000 Miles
* Numerous Ball Joints and Rod Ends?
* Replaced Wheel for peeling @ 25,000 Miles (actually all are peeling now except the one they replaced!)
* Rear Left Spring @ 45,000 Miles
Now it's been fairly smooth sailing for the past 1-2 years other than tires and snow tires. By the way, we run General AltiMAX Arctic
tires on our car (winter) and they're like glue on ice and snow. We love them and have driven a good 12,000-15,000 miles in all snow conditions last winter and this winter and they perform like a champ. I highly recommend them if they're available for your particular Mercedes. We don't have 4Matic, but you'd swear you have 4 wheel drive with these tires. Car stops in snow almost like dry pavement in summer.
Look forward to many more great advises !
We travel to camp on a lake in the winter located in the Adirondack Mountains, NY (Mercedes) and it's a safe and secure feeling vehicle for that purpose.