66RFE Governor Pressure Solenoid 2009-2018, remanufactured and ready to install. Fits the 66RFE. Ships fast from the USA.
If your gas Ram 2500, Power Wagon or chassis cab truck with the 66RFE is stuck in limp mode, banging into gear, or setting a string of solenoid and pressure switch codes, you may have landed here by searching for a 66RFE governor pressure solenoid. That part belongs to the old 47RE and 48RE four-speeds. The 66RFE replaced the governor with electronics, and the part that does that work is the solenoid block bolted to the valve body. This listing is a Sonnax remanufactured RFE solenoid block, part number 44836B, built for the gray-connector generation used from about 2010 until the 2019 redesign.
The 66RFE is the heavy-duty gas-engine member of the RFE family, and it has no throttle cable, no modulator and no governor. The controller reads engine torque, vehicle speed and gear, then fires the clutch solenoids on this block to make each shift. One solenoid in the same housing is a variable force unit that sets line pressure; pressure switches report which clutches actually filled, and that feedback is how the controller catches a slipping clutch or a stuck valve. On a truck that tows, the block gets a hard life. Heat breaks down the coils and the internal seals, and a block that leaks internally will drag pressure down across every gear.
Sonnax describes the gray pack as a five-solenoid design. Chrysler removed one solenoid and two checkballs and let the multi-select solenoid take over overdrive duty, which is why the gray block and the earlier white block are not interchangeable.
Check hot fluid level and condition, then verify the transmission control relay output and battery voltage, since one feed supplies all the solenoids. Watch desired and actual line pressure on a scan tool. Sonnax shows that an open pressure control circuit parks actual pressure at maximum with no response from the duty cycle. Before replacing the block for a pressure switch code, read our 66RFE limp mode causes and the 66RFE shift solenoid symptoms guide; worn valve body bores and a weak pump can set the same codes.
The block is listed for 2009-2018 65RFE, 66RFE, 545RFE and 68RFE units with the gray connector. GEARS Magazine lists the 66RFE in the Ram 2500, Power Wagon and chassis cab models. The 2009 end of that range is the catch: Sonnax gives both 2009 and 2010 for the gray-pack introduction, so pull the pan and look at the connector on your old block before you order. Gray is a match. A white connector means the earlier six-solenoid valve body, which a gray block cannot service. A blue connector means a 2019-up truck and a different part. Our 66RFE identification guide helps confirm what you have, or send us your year and VIN. Everything else for this unit is on the 66RFE parts page.
A heavy-duty truck that is coming apart this far is a good candidate for a 66RFE clutch module if the clutches are already worn, and if the gray connector on your truck turns out to need the alternate pack, the 2010-2018 remanufactured 66RFE pack is the other option we carry.
| Fits | 66RFE 2009-2018 |
| Part type | Governor Pressure Solenoid |
| Condition | Remanufactured |
| Brand | Sonnax |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. Governor pressure solenoids were used on the four-speed RE units. The 66RFE uses a solenoid block on the valve body for shift and pressure control, and this listing is that block.
It is listed for gray-connector 66RFE units from 2009 through 2018. Confirm the connector on your current block is gray before ordering.
No. Sonnax states the five-solenoid gray block cannot back-service the earlier six-solenoid design.
Sometimes, but pressure switch codes on RFE units are often caused by worn valve body bores. Test the valve body before replacing the block.
ATF+4 only, with the level set at operating temperature.
Yes. Clear codes and perform the quick learn with a scan tool so the controller adapts to the new solenoids.
