Valve body for the Mercedes 722.6 five-speed, sold as NAG1 in Chrysler, Dodge and Jeep. Fixes limp mode and harsh or missing gear changes.
Mercedes-Benz developed the 722.6 and then licensed the same five-speed to Chrysler, which badged it NAG1 - also written W5A580 or W5A380 - for the 300, Charger, Challenger, Magnum, Crossfire, Nitro and the Jeep Grand Cherokee and Commander. Underneath the different badge it is the same transaxle with the same valve body, which is why one part covers a Mercedes E-Class and a Dodge Charger built the same decade.
This valve body is the hydraulic routing center for the whole transaxle. Pump pressure flows through precision-bored passages and spool valves to apply each clutch pack and band on the command of the transmission control module, and the conductor plate bolted to the body carries the shift and pressure-control solenoids that actually execute each shift. When a bore wears or a solenoid seat degrades, pressure control gets inconsistent before the transmission fails outright, which is where the harsh and missing shifts start.
The classic complaint on this transaxle is not actually the valve body - it is the conductor plate's integrated speed sensors going open-circuit, which drops the transmission into limp mode in second or third gear on both the Mercedes and Chrysler versions. Our 722.6 valve body symptoms and testing guide covers how to isolate a hydraulic fault from a sensor one, and the 722.6 common problems and fixes guide runs through the full failure list across both the Mercedes and Chrysler applications.
Because this part is sold across two brands and well over a decade of production, match it by casting and connector rather than by year or model alone. On the Chrysler side it covers the 300 (2005-2011, 3.5L/3.6L/5.7L/6.1L), Crossfire (2005-2008, 3.2L), Challenger (2008-2011, 5.7L/6.1L), Charger (2006-2011), Nitro (2007-2010, 4.0L), Grand Cherokee (2005-2011) and Commander (2006-2010); on the Mercedes side it covers the CL500, CL550, CL600, E300, E320, E350 and S600 through 2011. Compare the manual valve end and solenoid pockets in the photos against your own unit, since the body changed in detail more than once across this range. The 722.6/722.9 transmission parts collection has specific-year listings if you would rather order by your exact build.
Drain the fluid and drop the pan first, disconnect the conductor plate connector, then remove the valve body bolts in a crossing pattern so the separator plate stays flat and the check balls do not shift. Refill with the Mercedes-specified 236-series ATF (Chrysler-badged units use the Chrysler-labeled equivalent fluid, not a generic Dexron), clear the stored codes, and run the adaptive relearn through a mix of light and moderate throttle before judging the result. Replace the W5A580 conductor plate with speed sensor at the same time if it has not already been tested, since a second failure means pulling the pan again, and consider the 722.6 shift kit if shift firmness was already marginal before these symptoms started.
| Transmission | Mercedes 722.6 / Chrysler NAG1 (W5A580) |
| Part number | 722.6 |
| Fits | Chrysler 300, Charger, Challenger, Grand Cherokee, Commander, Crossfire, Nitro, Mercedes E/CL/S |
| Exterior | Machined aluminum |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Yes. Chrysler licensed the Mercedes 722.6 and sells it as the NAG1 (also written W5A580 or W5A380). The hydraulics and the valve body are the same part under a different badge.
Chrysler 300 (2005-2011), Crossfire (2005-2008), Challenger (2008-2011), Charger (2006-2011), Nitro (2007-2010), Jeep Grand Cherokee (2005-2011) and Commander (2006-2010), plus Mercedes CL500/CL550/CL600, E300/E320/E350 and S600 through 2011. Match the casting and connector against the photos since the body changed across this range.
Banging or harsh engagement into gear, holding a single gear or missing the 2-3 upshift, slipping under load once hot, or limp mode with a stored solenoid code.
Check the conductor plate's speed sensors first. Open-circuit sensors are the most common cause of limp mode on this transaxle on both the Mercedes and Chrysler versions.
Mercedes-specified 236-series ATF on the Mercedes-badged units; the Chrysler-labeled equivalent fluid on the NAG1-badged units. Do not substitute a generic Dexron fluid.
One year from the date of install.
