2017 Mercedes-Benz GLS-Class Powertrain & Transmission Problems

My 2017 Mercedes-Benz GLS 450 is experiencing serious and unpredictable transmission behavior related to the valve body and shifting mechanism. The transmission sometimes fails to engage Park, shifts on its own without driver input or attempts to engage Reverse unexpectedly. On multiple occasions the vehicle has moved or rolled after being placed in Park and once it appeared to shift itself toward Reverse. This behavior is a clear safety risk as the vehicle can suddenly lose control or move unexpectedly. It happens intermittently, without any dashboard warnings and often resets temporarily after restarting the car. According to multiple owners posting on Mercedes-Benz forums (including MBWorld, BenzWorld, and Mercedes-Benz Owners Club discussions), this issue is common among GLS and other Mercedes models using the same transmission. Many owners report identical symptoms: transmission slipping into Neutral or Reverse, failure to engage Park or erratic shifting caused by a malfunctioning valve body, defective solenoids or Transmission Control Module (TCM) faults. Some have shared diagnostic codes such as P073E and P07B7 that point to reverse and park circuit errors. Mercedes technicians and independent repair specialists who have posted on these forums frequently identify the valve body assembly as the source of the issue. Common explanations include internal hydraulic pressure faults, electrical connector leaks or sensor failures inside the valve body. Owners have been quoted thousands of dollars for valve body replacements as i was billed $2300+. This problem is not isolated to my vehicle and appears to be a recurring design or manufacturing defect that affects multiple model years and platforms sharing this transmission. Because the vehicle can unexpectedly shift or fail to hold Park, it creates an immediate safety concern for both drivers and bystanders. I have video of this dangerous issue

REAR AXLE LOCK UP BRIEFLY MADE A SOUND LIKE SOMEONE REAR ENDED THE CAR AND SNAP THE LEFT SIDE REAR CV AXLE. VEHICLE IS AWD AND DOES NOT MOVE ON ITS OWN POWER.. SHOP TOW SUV AND ON THE AIR FOUND THE AXLE INNER JOINT JUST SPINS BUT CAR DOES NOT MOVE, THEY PULLED THE AXLE AND THE IS METAL BURNT INTO THE AXLE SHAFT SEEMS REAR DIFF LOCK UP, OIL WAS CLEAN ON THE DIFFERENTIAL.

REAR DIFFERENTIAL AXLE SEALS WERE DISTORTED, CAUSING FLUID TO LEAD OUT. THE SEALS APPEAR TO HAVE BEEN INSTALLED INCORRECTLY WHEN THE CAR WAS MANUFACTURED. SEALS HAVE BEEN REPLACED PRIOR TO ANY ADDITIONAL PROBLEMS WITH THE VEHICLE OR DRIVE TRAIN. DEALER REPLACED SEAL QUICKLY AND PROMPTLY. DEALERSHIP WAS A PLEASURE TO DEAL WITH.