722.9 Pump 2004, remanufactured and ready to install. Fits the 722.9. Ships fast from the USA.
If your Mercedes with the seven-speed 7G-Tronic is slow to pick up Drive or Reverse, slips once it is warm, or came apart with a scored converter neck and metal in the pan, the front oil pump belongs at the top of the parts list. This is a remanufactured 722.9 transmission oil pump, Mercedes part number 221 277 01 20 (also written A221 277 0120), for 2004-and-later 722.9 units. It is a complete pump assembly, so you are not reusing a worn housing or gear set.
The 722.9 is an electronically controlled seven-speed. Every shift is made by solenoids on the valve body metering oil to the clutches, and all of that oil starts at this pump. It is a crescent-style gear pump at the front of the case, turned by the torque converter neck whenever the engine runs. It feeds working pressure to the valve body, charges the converter and lockup clutch, and supplies cooler flow and lubrication. The electronics can only shape pressure that the pump has already made, so a worn pump shows up as soft, late or slipping shifts across the whole range rather than in one gear.
The 722.9 also has a well documented pump weakness. Transmission Digest and ATSG describe the original pump bushing seizing to the converter neck. Once that happens the drive gear can move off center, catch the crescent and destroy the pump, and the damage often reaches the converter housing as well. Mercedes later released a revised pump with a needle bearing in place of the bushing, listed under number 722 270 01 97.
Check the fluid level the factory way first, at operating temperature with the engine running and the car level, because a low level mimics a weak pump on this unit. Scan the transmission control module for stored faults; a solenoid or conductor plate fault points at the valve body, not the pump. If the pan holds metal and the converter neck shows galling or a blue heat mark, the pump has almost certainly been damaged. Our Mercedes pump failure guide walks through the pressure and noise checks, and the common problems and fixes guide covers the valve body faults that can look like pump trouble.
This pump is listed for 2004-and-later Mercedes 722.9 seven-speed automatics, with the listing also naming late 722.6 five-speed units. The 722.9 went into most rear- and all-wheel-drive Mercedes models from that era, including the C, E, S, CLS, ML and GL. Mercedes revised the pump during the 722.9 run, so compare the number cast or stamped on your old pump with 221 277 01 20, and read the transmission number from the case tag. If you are unsure, send us your year, model and VIN before you order. You can browse all of our Mercedes 722 transmission parts, and the 722.6 and NAG1 oil pump is listed separately for earlier five-speed units.
A pump that failed from debris usually means the valve body took a hit too. The 722.9 solenoid kit and 722.9 pressure control solenoid are worth having on hand when you open it up.
| Fits | 722.9 2004 |
| Part type | Pump |
| Condition | Remanufactured |
| 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 is listed for 2004-and-later 722.9 seven-speed transmissions as part number 221 277 01 20. Mercedes revised the pump during production, so match the number on your old pump or send us your year, model and VIN to confirm.
The best known failure is the original pump bushing seizing to the torque converter neck. The drive gear then moves off center, contacts the crescent and wrecks the pump, sometimes damaging the converter housing too. Low fluid level and debris from other failures also wear the pump.
Only if the converter neck is scored, galled or heat-marked. Inspect it carefully, because a damaged neck will wear out the new pump quickly. If the old pump came apart, have the converter cleaned or replaced since it will hold debris.
Mercedes specifies 236.14 fluid for 722.9 units built up to June 21, 2010. Later units take 236.15, or 236.15 or 236.16 depending on the engine. Check your production date and never mix the fluids.
Yes. Clear and relearn the transmission adaptations with a scan tool that can access the Mercedes transmission control module, then drive the car through all gears so shift quality settles in.
