How do I avoid hard shifting issues when installing a 7G-Tronic ATF change kit?

First, ensure that your transmission code is A89 or that your ATF is blue-in-color.

Secondly, it is critical to know that special tools and refilling procedures are required when servicing a Mercedes 7G-Tronic transmission. Using an OBD2 diagnostic scan tool to monitor transmission temperature when refilling transmission fluid is critical to ensure the temperature does not exceed 45 degrees Celsius during the procedure. If the fluid is above or below this temperature the fluid level in the transmission will be incorrect, causing the transmission to not shift correctly.

We recommend our customers have their Mercedes 7G-Tronic transmissions serviced by a certified ASE independent Mercedes specialist rather than with a quick lube change facility. This ensures the unique procedures required are followed and that the correct tools are used.