66RFE Transmission Cooler 1999, new and ready to install. Fits the 66RFE. Ships fast from the USA.
Read this first: although this item is filed under transmission coolers, it is not a cooler. It is a fluid service kit for the Chrysler RFE family, listed for 1999 and later 45RFE, 545RFE, 65RFE, 66RFE and 68RFE automatics in Chrysler, Dodge, Jeep and Ram vehicles. The kit is built around the four-wheel-drive style pan filter, a spin-on filter and a pan gasket, and it cross-references Mopar numbers 5013470AA, AB, AC and AE, 4799507, 4799662 and 5179267AC/AD. If your truck is running hot, shifting late after a long tow, or simply due for its pan drop, this is the box of parts that goes on the bench before the new fluid goes in.
The RFE units are fully electronic, and every clutch apply depends on clean, correctly pressurized ATF reaching small solenoid-controlled passages in the valve body. The pan filter is the pump's only protection: it sits in the sump and screens clutch material and metal before the pump draws fluid in. The spin-on filter is a second line of defense on the cooler circuit, catching debris that leaves the transmission so it does not settle in the cooler and come back. When either one loads up, pump suction suffers, line pressure becomes unstable and fluid flow through the cooler drops, which is where heat problems start. GEARS Magazine puts the cooler flow minimum for these units at one gallon per minute and notes that fluid life halves for every 20 degrees F above about 200 degrees F.
Pull the pan and read what you find. Fine gray sludge is normal wear; brass flakes, steel slivers or chunks of friction lining point to a mechanical failure that a filter will not fix. A pump that is wearing its gears will also load the filter quickly, so if you see bright metal, work through our 68RFE pump failure guide before you button the pan back up. If the complaint is heat rather than debris, check the cooler bypass and cooler flow; a stuck thermal bypass sends hot fluid straight back to the case no matter how clean the filters are.
The listing covers 45RFE, 545RFE, 65RFE, 66RFE and 68RFE units from 1999 forward and names the pan filter as the 4WD style. It also carries a note that it fits 2WD and 4x2 vehicles from 2010 on, so two-wheel-drive trucks built before 2010, which used a different pan and filter depth, should not assume a fit. The surest check is to compare the filter you remove with the photo and with the Mopar numbers above, or send us your year and VIN before ordering. Diesel Rams with the 68RFE are the most common buyers; browse the full 68RFE parts collection for other service items.
If you tow regularly, this is a good time to address the cooler circuit as well. The RevMax 68RFE thermal bypass valve upgrade keeps fluid moving through the cooler, and the 68RFE aluminum pan kit adds capacity on trucks that see heavy loads. For the full list of what tends to go wrong behind the Cummins, see our 68RFE Ram 2500 common problems guide.
| Fits | 66RFE 1999 |
| Part type | Transmission Cooler |
| Condition | New |
| 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.
No. Despite its catalog category, the item is a filter service kit: a 4WD-style pan filter, a spin-on filter and a pan gasket for the RFE transmission family. It does not include a cooler or cooler lines.
The kit is listed with the 4WD pan filter and a note that it also fits 2WD and 4x2 vehicles from 2010 on. Two-wheel-drive trucks built before 2010 used a different filter, so compare your old filter or send us your year and VIN first.
ATF+4 only. Chrysler's service instructions for this transmission family specify ATF+4 and require the fluid to be at least 160 degrees F when the level is set, so check the level hot with the engine running.
Only if the cause is restricted flow from a clogged filter. If the pan holds metal flakes or friction material, or the truck sets solenoid or pressure switch codes, the filter is a maintenance item and the real fault is elsewhere.
Follow the maintenance schedule for your vehicle and shorten it if you tow or plow. Heavy-duty use builds heat, and heat is what breaks down ATF and loads up the filters fastest.
