66RFE Solenoid Kit, new and ready to install. Fits the 66RFE. Ships fast from the USA.
A 66RFE that suddenly holds one gear, slides through a shift, or lights the check engine light with pressure switch codes often has a solenoid pack that can no longer deliver what the computer is asking for. This listing is a new Mopar-branded 66RFE solenoid kit. The product photo shows the pack together with a pan filter and pan gasket, so you can service the sump in the same job. This page focuses on the hydraulic side of the repair: how the pack feeds the clutches, which mistakes cause problems after a pack swap, and how to tell a pack failure from a pressure supply problem.
The 66RFE is one of the six-speed RFE units that Sonnax lists with the 65RFE and 68RFE. Line pressure from the pump is regulated by the variable line pressure solenoid, then routed through the valve body to the clutch solenoids on the pack. Each clutch solenoid opens or vents its circuit to apply or release a clutch, and each circuit has a pressure switch that confirms the clutch really filled. Sonnax gives the switch behavior as closing near 22 psi and opening near 11 psi. So a 66RFE pack does two jobs at once: it moves oil, and it reports whether the oil got there. That is why a weak solenoid or a leaking seal produces both a driveability complaint and a code.
Start with line pressure. GEARS Magazine puts a healthy RFE idle reading at 60 to 70 psi with commanded and actual pressure close together. If actual pressure cannot follow commanded, the pump, regulator or a cross-leak may be the cause, and our RFE pump failure guide covers that path. Sonnax also explains that a stuck-high line pressure reading can set P0933 or P0869. If pressure tracks normally but one clutch circuit keeps reporting a fault, the pack or its gasket is the likely failure. Our RFE solenoid testing guide shows how to finish the check with a meter.
This kit is listed for the 66RFE without a year range, so match it before you buy. Transmission Digest identifies three pack generations in this family by the color of the pass-through connector: white, gray and blue. The gray pack dropped the overdrive solenoid, and the 2019-up blue pack added a separate reverse clutch solenoid and moved converter clutch control to its own solenoid. The pack in this photo has a light-colored connector rather than a blue one, so it belongs with the earlier packs. Match your connector color, or send us your year and VIN and we will check it for you. For a lower-cost alternative on the same unit, see the 66RFE solenoid kit for 1999-2018, and browse the rest of the parts on the 66RFE parts page.
| Fits | 66RFE |
| Part type | Solenoid Kit |
| Condition | New |
| Brand | Mopar |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. Use a new gasket and make sure it matches your pack generation. The gray and white packs share one gasket and the blue pack uses another; mixing them causes a bind-up or a neutral 2-3 shift.
Compare commanded and actual line pressure on a scan tool. A healthy RFE idles around 60 to 70 psi with the two values close. If actual cannot follow commanded, look at the pump and regulator first.
The pictured pack has a light-colored connector that matches the earlier design. 2019-up units use a blue-connector pack with an added reverse clutch solenoid, so this kit is not intended for them. Send us your year and VIN to confirm.
ATF+4, with the level checked at operating temperature.
Yes. Clear codes and run a quick learn, then drive 10 to 15 shift cycles so the computer adapts to the new solenoids.
