Expert Mercedes-Benz S-Class transmission service in Chicago. Free computer diagnostic, 2-year / 24,000-mile warranty on rebuilds, all years.
We will contact you as soon as a service member is available by call, text, or email.
W220 S-Class (1999 - 2005): 5G-Tronic (722.6 NAG1) 5-speed automatic. W221 S-Class (2006 - 2013): 7G-Tronic (722.9 NAG2) 7-speed automatic. W222 S-Class (2014 - 2020): 7G-Tronic+ (722.9) or 9G-Tronic (722.9 AMG variant). W223 S-Class (2021+): 9G-Tronic nine-speed automatic (722.9 9AT). S-Class Plug-in Hybrid: Modified 9G-Tronic with electric motor integration.
S-Class conductor plate work requires genuine Mercedes-Benz conductor plate assemblies and MB-Star diagnostic equipment for proper adaptation coding after installation. We stock 722.9 conductor plates and have MB-compatible diagnostic equipment. For W220 NAG1 (722.6), solenoid pack replacement is the primary repair. AMG models require the same procedures with additional attention to cooling system integrity.
722.9 (7G-Tronic): MB 236.14 or 236.15 fluid. 9G-Tronic: MB 236.17 fluid. NAG1/722.6: MB 236.14 or Mopar ATF+4. Change every 40,000 miles regardless of Mercedes 'lifetime' designation.
Conductor plate replacement: 1 - 2 days. Valve body rebuild: 2 - 3 days. Full rebuild: 4 - 5 days.
Every vehicle needs diagnosis before anyone can promise a repair path. These are the situations we help organize before you decide what to do next.
Tell us when it happens, whether reverse still works, and if warning lights are on. A scan and fluid check come before guessing at a rebuild.
Fluid condition, leak location, and driving distance matter. If the vehicle is slipping badly or overheating, towing may be the safer next step.
A failed solenoid, valve body, converter, or internal clutch problem can lead to very different repair paths. The goal is a clear diagnosis and written estimate.
On a 722.9 7G-Tronic S-Class, limp mode almost always means conductor plate failure. The transmission protects itself by locking into a single gear. Don't delay - get it diagnosed immediately.
Dealer pricing: $2,000 - 3,500 for conductor plate replacement. Our price: $900 - 1,500 for the same service with MB-Star adaptation coding.
Valve body wear - the solenoid bores wear independently of the conductor plate. When both need service, the total repair runs $1,400 - 2,200 for valve body rebuild.
The 9G-Tronic is a more sophisticated unit, but it still requires fluid changes every 40,000 miles. Neglected fluid accelerates solenoid bore wear.
Yes - we use MB-compatible diagnostic equipment that reads all Mercedes fault codes and performs conductor plate adaptation coding.
Same-day appointments available. Honest estimates, no surprises. We've been doing this since 1987.
