66RFE Overhaul Kit 2007-2018, new and ready to install. Fits the 66RFE. Ships fast from the USA.
If you are tearing down the six-speed behind a 5.7L or 6.4L Hemi in a Ram 2500, a Power Wagon or a 3500 chassis cab, the transmission on your bench is a 66RFE, and this is the gasket and seal set that puts it back together. The photo shows a TransTec overhaul kit in its sealed bag, listed under reference 81000518. It is the kit you buy when the unit is already coming apart for slipping, a burnt pack or a leak that has spread to more than one place, and you want every rubber and paper seal renewed at once instead of finding the next weep a month after the truck goes back to work.
Chrysler built the 66RFE for 2012 by fitting 68RFE internals and the 68RFE gearset into a 545RFE-style case, giving the gas heavy-duty Rams the same six ratios as the diesel trucks. Like every RFE unit it uses no bands. Each gear comes from clutch packs that are applied by hydraulic pistons, and the fluid that reaches those pistons has to pass sealing rings on rotating shafts and drums, piston lip seals, O-rings and the case and pan gaskets on the way. An overhaul kit is that sealing layer. When those parts harden from heat and age, apply pressure bleeds off, the packs take longer to fill and the controller sees slip it cannot correct. Frictions and steels are not part of an overhaul kit; they are bought separately or as part of a master kit.
A leak at a single external seal does not need a full overhaul, so find where the fluid is actually coming from first. For slip, read the pan and scan for codes before assuming worn seals. Sonnax names the solenoid switch valve bore plug as a wear point on the 45RFE through 68RFE family, along with the stator overdrive dribbler valve, and both can burn an overdrive clutch on a unit with good seals. Our RFE valve body testing guide covers how to separate a valve body leak from a mechanical failure, and the pump failure guide explains the low-pressure signs that look like a seal problem.
The listing covers the 66RFE with a 2007-2018 range. The 66RFE itself was introduced for the 2012 model year, so for a gas Ram the years that apply are 2012-2018: the Ram 2500 and Power Wagon with the 5.7L, the 3500 chassis cab with the 5.7L, and from 2014 the Ram 2500 with the 6.4L. The earlier start of the range reflects how the kit is catalogued for the RFE six-speed family, not a 66RFE built before 2012. A 2019-up truck uses a later solenoid and valve body design, so confirm before ordering. Match the reference number 81000518 against the kit your shop specifies, or send us your year and VIN and we will check it. Pumps, solenoids and valve bodies for these trucks are grouped on our 68RFE and 66RFE collection page.
| Fits | 66RFE 2007-2018 |
| Part type | Overhaul Kit |
| Condition | New |
| Brand | OEM |
| Reference | 81000518 |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
The 66RFE was introduced for 2012, so a 2010 gas Ram 2500 does not have one even though the listing range starts at 2007. Check the transmission tag or send us your VIN and we will tell you which unit and kit you need.
No. An overhaul kit is the gasket and seal set: sealing rings, lip seals, O-rings and gaskets. Frictions, steels and filters are purchased separately or as part of a master rebuild kit.
Not exactly. The 66RFE uses 68RFE internals and gearset inside a 545RFE-style case and sits behind the 5.7L and 6.4L gas engines. The 68RFE is the 6.7L Cummins diesel unit. Seal kits are not automatically interchangeable, so match the reference number or VIN.
ATF+4 only. Set the level with the fluid at operating temperature and recheck it after the first few drive cycles.
Yes. Clear codes and run the quick learn procedure with a capable scan tool so the controller adapts to the new clutch fill times.
