Vehicle is a 4 wheel drive SUV, having the Mercedes-Benz "4Matic" drivetrain, has it's Center Differential Planetary Gearset (With Integral Clutch Pack) in failure. Mercedes is clearly aware that this is a drivetrain component that fails prematurely as there is a Technical Service Bulletin (LI28.00-P-051499) that provides methodology for diagnosing the failure for 4Matic equipped vehicles from 2003 to 2016, specifically listing 83 different 4Matic equipped vehicles. Particular caution is called out as to special lubrication required prior to assembling the component into the drive train. Very likely that the root cause of the widespread failures was the part not being installed correctly. Though the failure evidences initially by front wheel vibrations and shuddering at low speed, it is a latent serious safety issue in that the component could fail catastrophically when stressed, i.e., hard acceleration when merging onto a highway, at best causing a sudden imbalance in front/rear propulsion resulting in an affected vehicle compromised in its steering, or at worst locking up front or rear wheels resulting in a spin out. Mercedes has replaced this equipment under warranty for an unknown number of vehicles, but refuses to acknowledge how widespread the problem is. Mercedes Customer Assistance says "no recall' so refuses to address the issue and flatly told me to take it up with the NHTSA. Public safety dictates that all affected vehicles need to be inspected for the failure and these defective components replaced as a recall.

- Old Lyme, CT, USA

The vehicle will not engage in D or R mode. Unable to drive. Error message in combi display = "service required, do not shift gears, visit dealer". the car was already three times at the Mercedes dealer & repair shop for the exact same problem, this is the fourth incident.

- Greenville, SC, USA

The vehicle will not engage in D or R mode. Unable to drive. Error message in combi display = "service required, do not shift gears, visit dealer". the car was already twice at the Mercedes dealer & repair shop for the exact same problem, this is the third incident.

- Greenville, SC, USA