722.9 Overhaul Kit 2005-2010, new and ready to install. Fits the 722.9. Ships fast from the USA.
This is a new overhaul kit with a matching piston kit for the Mercedes-Benz 722.9 seven-speed automatic, listed for 2005 through 2010. That span covers the first full production years of the 7G-Tronic in rear-drive and 4MATIC C, E, S, CLS, ML, GL and R-Class models. The kit is for a unit that is coming apart anyway: it leaks, slips when hot, has lost apply pressure with age, or drops into neutral as it shifts into third. Pairing the reseal with new pistons in one purchase means you are not reusing the molded pistons that commonly fail in this transmission.
The 7G-Tronic shifts entirely with clutches and brakes: three rotating clutches (K1, K2, K3) and four brakes (B1, B2, B3, BR), with no bands or sprags. Each pack is applied by a piston, and that piston only works while its lip seals and the sealing rings feeding it hold pressure. With age the rubber hardens and shrinks, the rings wear, and the control unit has to work harder to finish each shift until it starts setting faults. The overhaul portion renews the gaskets, piston seals, sealing rings and O-rings throughout the case. The piston kit replaces the pistons themselves. Frictions, steels, filter, torque converter and valve body are not part of this kit, so plan for those based on what you find.
Do not start with the clutches. Gears magazine found that most 722.9 failures begin with cut or hardened O-rings on the solenoid tips, and a leaking solenoid will keep burning clutches after any rebuild. Mercedes-Benz diagnostic bulletin LI27.00-P-051451 also says to read out the control unit's log and EEPROM data before any adaptation reset. Scan, save that data, check level and condition, then drop the pan. Lining material and metal in the pan mean the unit needs to come apart, and this kit plus frictions is the right order. Clean fluid with a shift complaint points at the solenoids and valve body first. Our pressure control solenoid symptoms guide explains how pressure control problems look from the driver's seat, which helps separate an electrical fault from worn seals.
The listing names the 722.9 and 2005-2010. Inside that range Mercedes ran several torque versions, and some early units received the updated K1 drum and stator support. Piston and seal shapes follow those internal versions, so lay the kit beside your parts during teardown, and send us your year and VIN if you want us to check it first. For a 4MATIC unit that also needs frictions, see the 722.9 4MATIC overhaul kit with frictions, pistons and filter. Everything else for the 722 family is in the 722.6 and 722.9 collection.
| Fits | 722.9 2005-2010 |
| Part type | Overhaul Kit |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It combines a 722.9 overhaul kit, the gaskets, seals, sealing rings and O-rings, with a piston kit. Frictions, steels, filter, torque converter and valve body are not included.
It is listed for the 722.9 7G-Tronic from 2005 through 2010. Internal versions vary within those years, so compare the kit to your teardown or send us your year and VIN.
The molded pistons are a known weak point. ATRA's Gears magazine reports that a failed K1 piston usually makes the transmission drop into neutral going into third.
It fixes slip caused by lost apply pressure from worn seals or failed pistons. Burnt clutch packs also need new frictions, and a leaking solenoid must be resealed or the slip will return.
Use the MB-approved fluid specification your transmission was built for. Check the fill label or your service records, and do not mix 236.14 and 236.15 fluids in the same unit.
