Transmission Cooling

The transmission fluid cooling system, without an auxiliary transmission fluid cooler, consists of:

an in-tank fluid cooler inlet tube.
a non-repairable in-tank transmission fluid cooler.
an in-tank fluid cooler return tube.

The transmission fluid cooling system, with an auxiliary transmission fluid cooler, consists of:

an in-tank fluid cooler inlet tube.
a non-repairable in-tank transmission fluid cooler.
an auxiliary fluid cooler inlet tube.
an auxiliary transmission fluid cooler.
an auxiliary fluid cooler return tube.

The transmission fluid flows from the transmission to the in-tank transmission fluid cooler, to the auxiliary transmission fluid cooler and returns to the transmission.

For fluid cooler flow testing, backflushing and cleaning procedures, refer to TRANSMISSION FLUID COOLER or TRANSMISSION FLUID COOLER FLOW TEST .

4R70E, 4R75E Transmissions With Auxiliary Transmission Fluid Cooler

Fig 1: Identifying 4R70E, 4R75E Transmissions With Auxiliary Transmission Fluid Cooler

Courtesy of FORD MOTOR CO.

4R70E, 4R75E Transmissions Without Auxiliary Transmission Fluid Cooler

Fig 2: Identifying 4R70E, 4R75E Transmissions Without Auxiliary Transmission Fluid Cooler

Courtesy of FORD MOTOR CO.

6HP26 Transmission With Auxiliary Transmission Fluid Cooler

Fig 3: Identifying 6HP26 Transmission With Auxiliary Transmission Fluid Cooler

Courtesy of FORD MOTOR CO.

6HP26 Transmission Fluid Fill Procedure

CAUTION: The vehicle should not be driven if the fluid level is low as internal failure could result.

NOTE:

If the vehicle has been operated for an extended period, at high highway speeds, in city traffic, during hot weather or while pulling a trailer, the fluid needs to cool down to obtain an accurate reading.
The transmission fluid temperature must not be allowed to exceed 50°C (122°F) when checking the fluid level. The fluid temperature should be between 30°C-50°C (86°F-122°F) when checking the fluid level.

This vehicle is not equipped with a fluid level indicator. An incorrect level may affect the transmission operation and could result in transmission failure.

Under normal circumstances, the fluid level should be checked during normal maintenance. If the transmission starts to slip, shifts slowly or shows signs of fluid leaking, the fluid level should be checked.

With the transmission in P (PARK), the engine at idle and foot pressed on the brake, move the range selector lever through each gear and allow engagement of each gear. Place the transmission range selector lever in the P position.
With the vehicle idling (600-750 rpm) in PARK, position it on a hoist.

Fig 4: Locating Fluid Fill Plug
Courtesy of FORD MOTOR CO.

CAUTION: The fluid fill plug located on the side of the transmission is near the exhaust system. The exhaust will be extremely hot during this procedure. Use care when working near the exhaust and the heat shields.

Fig 5: Locating Fluid Fill Plug Hole

Courtesy of FORD MOTOR CO.

Remove the fluid fill plug located on the RH rear side of the case near the transmission electrical connector.

CAUTION:

The use of any other transmission fluid can result in the transmission failing to operate in a normal manner or transmission failure.
The fluid fill plug located on the side of the transmission is near the exhaust system. The exhaust will be extremely hot during this procedure. Use care when working near the exhaust and the heat shields.

Fill the transmission.
- Add clean automatic transmission fluid to the transmission through the fluid fill hole. Stop when the fluid runs out of the bottom of the hole.

Install the fluid fill plug.
- Tighten to 35 N.m (26 lb-ft).
Move the transmission range selector lever through all the gear ranges, checking for engagements.

If more fluid is needed, start the engine. Remove the fluid fill plug on the side of the case, fill with clean automatic transmission fluid until fluid just starts to dribble out of the hole and reinstall the fill plug.