Adjusting your speedometer and transmission module settings after installing larger tires on your Mercedes-Benz G55K is crucial for maintaining optimal performance and safety. This process, often requiring specialized diagnostic tools like MB Xentry, ensures accurate speed readings and proper electronic stability program (ESP) and electronic traction control (ETC) functionality.
One user shared their experience of upgrading to 32.7-inch tires (286/65/18) on their G55K with stock AMG wheels. Initially, they observed a significant decrease in ESP and ETC responsiveness after installing tires with a 10% higher profile. Adjusting the settings at an MB shop provided some improvement, but a more substantial change occurred after utilizing a Star Diagnosis system.
Using the Star Diagnosis system, the user’s mechanic maximized the tire size settings in both the ESP module and the transmission module. This adjustment dramatically improved the ESP and ETC performance, restoring them to levels even better than with the stock tires. The transmission module adjustment, specifically setting it to the largest tire size (around 35 inches), optimized the gear ratios for the larger diameter tires.
The user reported that with the 32.7-inch tires and adjusted settings, the vehicle achieved full suspension flex and steering without any rubbing issues. Furthermore, the electronic systems, including ESP and ETC, functioned flawlessly, even under demanding driving conditions.
The user recommends calibrating the speedometer to 33 inches and adjusting the transmission module to its highest setting when using 32.7-inch tires on a G55K. This configuration reportedly allows for aggressive cornering at high speeds with responsive and effective ESP intervention. While specific numerical settings weren’t provided, the emphasis lies in maximizing the tire size parameters within both the ESP and transmission modules using diagnostic tools like MB Xentry or Star Diagnosis. This recalibration ensures accurate speed readings and optimal performance of the vehicle’s electronic stability and traction control systems. This process is crucial for maintaining safety and maximizing the performance benefits of larger tires on the G55K.
