722.9 7G-Tronic Master Rebuild Kit for Mercedes-Benz

Master overhaul kit for the Mercedes-Benz 722.9 seven-speed automatic, the transmission Mercedes calls 7G-Tronic (internal code NAG2). It went into rear-drive and 4MATIC cars and SUVs from roughly 2004 on across the C, E, S, CLK, CLS, SL, ML, GL and R lines, so this is the box you are into any time one of those comes in slipping, flaring on the 2-3, or throwing a limp-home code after a hard-parts failure. The kit carries the OEM reference T18900A, which combines the T18902A friction pack, T189080A, and T189081A sub-sets.

What is in the box is the wear that a rebuild replaces: the clutch friction plates and steel plates for the drive packs, the full gasket and pan gasket set, and the O-rings and sealing rings that ride on the pistons and the pump. When you tear a 722.9 down for burnt frictions or contaminated fluid, these are the parts that do not go back in, and having the matched set on the bench keeps you from stopping halfway to chase a single seal.

Use it the way you would any full rebuild: clean and inspect the drums and the pump, air-check the circuits, then reload the drive packs with the new frictions and steels and reseal every piston as you stack the unit back up. This kit covers the soft parts and clutches; it does not include the conductor plate, valve body, or torque converter, so inspect those separately and order them if the failure calls for it.