722.6 Solenoid Kit, used and ready to install. Fits the 722.6. Ships fast from the USA.
When a five-speed Mercedes, a C230, E320 or ML430, or a Chrysler, Dodge or Jeep with the NAG1 version, stops shifting, holds one gear until you shut it off, or comes back up in second every time you restart it, the shift solenoids are high on the suspect list. This is a used, OEM 722.6 solenoid set of six pieces, pulled from a 2001 ML430, covering the three shift solenoids, the two pressure regulating solenoids and the lockup solenoid. It is the budget way to put factory parts back in a 722.6 when one or more of yours has failed.
The 722.6 splits its solenoids into two jobs. Three are simple on-off shift solenoids: the 1-2/4-5 solenoid (Y3/6y3), the 2-3 solenoid (Y3/6y5) and the 3-4 solenoid (Y3/6y4). Each is switched on only for the moment of its shift and is fed roughly 50-55 psi of solenoid shift pressure. The other two, the modulating pressure solenoid (Y3/6y1) and the shift pressure solenoid (Y3/6y2), are variable regulators that set how firm each shift feels and how much line pressure holds the clutches. The sixth controls torque converter lockup. Because the shift solenoids rest off once a gear is engaged, a solenoid circuit fault leaves the transmission stuck in whatever gear it was in, then defaulting to second after a restart.
The 722.6 has no pressure taps, so diagnosis is by scan tool and resistance check. Pull the codes, note which gear range they name, and ohm each solenoid at the case connector against the factory values. Then pull the connector and look for fluid inside it. On 2004-and-later NAG1 vehicles the adapter sleeve O-rings leak, oil reaches the plug, and you get intermittent solenoid codes from perfectly good solenoids. Also remember that a solenoid with a shrunken O-ring will pass an ohm test and still leak pressure. Our 722.6 shift solenoid guide covers the full test, and the 722.6 pressure control solenoid guide explains how to tell a regulator fault from valve body bore wear.
This set fits the 722.6 five-speed, which Mercedes, Chrysler, Dodge and Jeep shared across many models; the donor was a 2001 ML430. The solenoid family is common across the 722.6, but connector and housing details changed over the years, so compare your old solenoids to the photo before installing, or send us your year and VIN and we will check it. If you want a set listed by year, see the 722.6 solenoid kit for 2001-2005, or browse everything for this transmission on the 722.6 and 722.9 parts page.
| Fits | 722.6 |
| Part type | Solenoid Kit |
| Condition | Used |
| 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.
Six used OEM solenoids: the three shift solenoids (1-2/4-5, 2-3 and 3-4), the modulating and shift pressure regulating solenoids, and the torque converter lockup solenoid.
The NAG1 is the Chrysler-built version of the 722.6 and shares the solenoid layout. Compare connectors and housings with the photo or send us your VIN to confirm.
Often it is a solenoid or its circuit, since the 722.6 defaults to second after a fault and a restart. Check the case connector for oil and ohm the solenoids before replacing them.
Yes. The O-rings shrink with heat and leak pressure even when the coil tests good. Fit new O-rings on every solenoid you install.
Clear the codes and reset the adaptation values with a scan tool before the road test so the module relearns with the replacement parts.
