722.4 Pump 1984-1997, remanufactured and ready to install. Fits the 722.4. Ships fast from the USA.
A Mercedes 190E, 190D or early C-Class with the four-speed 722.4 automatic that leaks ATF from the bellhousing, engages Drive slowly after sitting, or slips once it is hot often has a tired front pump. This is a remanufactured 722.4 front oil pump for 1984-1997 units, supplied with a new pump seal and O-ring, so you can put a known-good pump in instead of rebuilding a worn housing on the bench.
The 722.4 (internal code W4A020) is a hydraulically controlled four-speed. Its front pump bolts to the front of the case and is driven by the torque converter hub, so it turns whenever the engine runs. Every bit of pressure the transmission uses comes from it: line pressure to apply the clutches and bands, converter charge, cooler flow and lubrication. Shift feel on this unit is set hydraulically, with a vacuum modulator reading engine load to adjust pressure. That means a pump that cannot hold volume hurts everything at once, and no amount of modulator adjustment will make up for it. The pump also carries the front seal that rides on the converter hub and the outer O-ring that seals it to the case, which is why so many 722.4 leaks trace back to this one part.
Rule out the cheap causes first. A cracked vacuum line or a ruptured modulator diaphragm can cause harsh or late shifts and will pull ATF into the engine, and a low fluid level alone can mimic pump wear. A drip at the bellhousing should be traced with the inspection cover off: wet at the converter hub points to the pump seal or O-ring, while oil running down from above may be the engine rear main seal. If the seal and O-ring are new and the leak continues, inspect the pump housing for porosity at the O-ring groove, which calls for a replacement pump. Our Mercedes pump failure symptoms guide is written around the five-speed 722.6 that replaced this unit, but the pressure checks and noise diagnosis carry over.
This pump is listed for the Mercedes-Benz 722.4 four-speed automatic, 1984-1997. The 722.4 was used mainly behind the four- and six-cylinder engines in the W201 190-series and the early W202 C-Class, and in some W124 models. The housing pictured carries the Mercedes number 201 277 03 20. Mercedes built many 722.4 variants, so read the six-digit transmission number that starts with 722 from the tag at the pan rail on the passenger side and compare it with your old pump, or send us your year, model and VIN before ordering. The rest of our 722-family parts are on the 722 transmission parts page.
If the old pump failed from debris or burnt fluid, the clutches are likely damaged too. The 722.4 master rebuild kit and the 722.4 banner rebuild kit supply the frictions, gaskets and seals for a full overhaul while the unit is out.
| Fits | 722.4 1984-1997 |
| 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.
The 722.4 four-speed was used mainly in the W201 190-series and the early W202 C-Class, and in some W124 models, through about 1997. Mercedes built many 722.4 variants, so check the six-digit 722 number on your transmission tag or send us your year, model and VIN.
Yes. This remanufactured pump is supplied with a new pump seal and O-ring so the most common leak points are fresh on install.
Pull the bellhousing inspection cover and look at where the oil is. Fluid that is red and concentrated at the converter hub points to the pump seal or O-ring. Oil running down the back of the engine block points to the rear main seal.
No. The torque converter has to come off first, and that requires removing the transmission from the car.
Inspect the converter hub for grooving, replace the filter and pan gasket, and check the vacuum modulator and its line. If the fluid was burnt or full of debris, plan on a full rebuild kit at the same time.
No. The 722.6 is a different, electronically controlled five-speed that replaced the 722.4, and its pump is not interchangeable. Match your transmission number before ordering.
