Tools you need for transmission fluid on a 2009-2018 Ram 1500

On the DS-generation Ram the job splits two ways. Trucks with the 545RFE, 65RFE or 66RFE behind the 4.7 or 5.7 have a deep steel pan held by 10 mm bolts and two filters inside it, so most people drop the pan and do filters at the same time. Trucks with the 845RE eight-speed (most 2013 and later 3.6, 5.7 and EcoDiesel) have a shallow aluminum pan with the filter built in, so a service is just a center drain plug with an 8 mm hex bit and a refill through the standpipe.

The thing people get wrong is the refill. Chrysler deleted the dipstick on most 2013-up trucks, and the level is only correct when the fluid sits in a narrow temperature window (about 110-120 F on the RFE, around 104 F on the eight-speed) with the engine idling in Park. Without a scan tool reading transmission temperature you are guessing, and guessing usually means overfilling and chasing a shift complaint you created. Also open the fill plug before you drain a single drop; a seized fill plug turns an easy afternoon into a tow.

Complete tool and parts list

Differences within the 2009-2018 generation

4.7L and early 5.7L trucks (545RFE/65RFE/66RFE) need 10 mm sockets for the steel pan plus two in-pan filters and ATF+4; 2013-up 3.6L, 5.7L and 3.0L EcoDiesel trucks with the 845RE need an 8 mm hex bit for the pan drain and fill plugs and the ZF 8/9-speed fluid instead. 2009-2012 trucks generally have a dipstick and can be filled through the tube; 2013-up generally do not and require the side or pan fill plug plus a scan tool for the temperature check.

Torque specs

How the job goes

1. Identify your transmission: 4.7L and early 5.7L trucks use the 545RFE (65RFE from about 2012, 66RFE on heavy-duty applications); 2013+ 3.6L, 5.7L and 3.0L EcoDiesel trucks mostly use the 845RE eight-speed with a shallow aluminum pan. The refill procedure is different for each.
2. Buy the correct fluid and enough of it: about 5-6 quarts for a drain and fill, 11-13 quarts if you ever go deeper. RFE units take ATF+4; the 845RE takes the Mopar ZF 8/9-speed fluid.
3. Drive the truck 10-15 minutes so the fluid is warm and suspended debris drains out, then park on level ground, chock the wheels and lift evenly. Keeping the truck level matters for the level check later.
4. Locate and loosen the fill point BEFORE you drain anything. On dipstick trucks that is the dipstick tube. On no-dipstick RFE trucks it is a plug on the left side of the case. On the 845RE it is a plug on the pan. If you cannot get it open, you cannot refill.
5. 845RE (8-speed): position the drain pan, remove the center drain plug with the 8 mm hex bit and let roughly 5 quarts out. The pan and filter are one assembly and are not routinely dropped for a simple service. Reinstall the plug with a new seal.
6. RFE units with a pan drain plug: remove the plug, drain, then decide whether to drop the pan for filters. RFE units without a drain plug: loosen all 10 mm pan bolts a few turns, remove all but the bolts at one corner, and pry that corner down gently so fluid runs into the pan.
7. Once drained, remove the remaining pan bolts and lower the pan. Expect another cup or two of fluid. Note the color and smell; heavy dark sludge or friction material means a deeper problem than a fluid change.
8. Pull the primary in-pan filter straight down (it is a press fit with an O-ring in the valve body) and remove the secondary cooler-return filter. Install both new filters with the new seals fully seated.
9. Clean the magnet on the pan floor, wipe the pan and the case sealing flange with non-chlorinated cleaner and lint-free towels, then fit the new gasket dry unless the procedure calls for a sealant bead.
10. Reinstall the pan and snug the 10 mm bolts by hand in a crisscross pattern, then torque to 105 in-lb (12 Nm). These thread into aluminum; over-torquing warps the flange and causes leaks.
11. Refill with the pump or funnel: put back in the amount you measured out, then add about a half quart. Refilling through a small side plug is slow, so expect 20-30 minutes.
12. Start the engine with your foot on the brake and shift slowly through P-R-N-D and back, holding a few seconds in each range to fill the circuits, then return to Park and let it idle.
13. Check the level at the specified temperature. With a scan tool watch transmission fluid temperature: the RFE check window is roughly 110-120 F and the 845RE is checked near 104 F (40 C). Fluid too cold or too hot gives a false reading.
14. On the 845RE, with the engine idling and the fluid at temperature, remove the fill plug; a light dribble means correct level, no fluid means add until it just trickles out. On dipstick trucks read the hot side of the stick. On no-dipstick RFE trucks, the level is set when fluid just seeps at the fill plug at temperature.
15. Reinstall the fill plug, shut off, check for leaks at the pan and plug, lower the truck, and test drive. Recheck for leaks after a few heat cycles and dispose of the old fluid at a recycling center.

Watch out

Pan bolt size (10 mm) and RFE pan torque (105 in-lb) are solid across the generation, and the 8 mm hex plug and temperature-based level checks match factory procedure, but plug torque values and whether your specific truck has a pan drain plug or a dipstick vary by build date, so confirm against the FSM or the label on your transmission before final torque.

Other jobs on the 2009-2018 Ram 1500

Transmission Fluid Change on other vehicles