Dodge RAM 1500 2018 Diesel Supplement page 205

Use the following procedure to check the transmission
fluid level properly:
1. Monitor the transmission temperature using the instru-
ment cluster display, and operate the vehicle as required
to reach the normal operating temperature. If the trans-
mission is not functioning properly, or the vehicle
cannot be driven, see the NOTE and CAUTION below
about checking the fluid level at colder temperatures.
2. Park the vehicle on level ground.
3. Run the engine at normal idle speed for at least 60
seconds, and leave the engine running for the rest of this
procedure.
4. Fully apply the parking brake and press the brake pedal.
5. Place the gear selector momentarily into each gear
position (allowing time for the transmission to fully
engage in each position), ending with the transmission
in PARK.
6. Remove the dipstick, wipe it clean and reinsert it until
seated.
SERVICING AND MAINTENANCE 203
7. Remove the dipstick again and note the fluid level on
both sides. The fluid level reading is only valid if there
is a solid coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be full of fluid if
the actual level is at or above the hole. The fluid level
should be between the "HOT" (upper) reference holes
on the dipstick at normal operating temperature. If the
fluid level is low, add fluid through the dipstick tube to
bring it to the proper level. Do not overfill. Use ONLY
the specified fluid (see Fluids And Lubricants for fluid
specifications). After adding any quantity of oil through
the dipstick tube, wait a minimum of two minutes for
the oil to fully drain into the transmission before re-
checking the fluid level.
NOTE: If it is necessary to check the transmission below the
operating temperature, the fluid level should be between the
two "COLD" (lower) holes on the dipstick with the fluid
at 60-70°F / 16-21°C for 68RFE transmission, or 68-86°F /
20-30°C for AS69RC transmission. Only use the COLD region
of the dipstick as a rough reference when setting the fluid
level after a transmission service or fluid change. Re-check
the fluid level, and adjust as required, once the transmission
reaches normal operating temperature.
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