Tech Features

This section contains bulletins and pertinent information for installers or repair facilities. Many of the bulletins in this section deal with very common installation or unit problems. Always check for pertinent bulletins before beginning any installation or if a problem occurs with a unit. Check back often. We add bulletins as information becomes available. If you have any questions please call the warranty department at 800-841-6060 or email us at
2000-2003 Thunderbird, Explorer
New Rotunda Tool for Checking Fluid Level and Filling Transmissions
5R55N, 5R55S & 5R55W
New Rotunda Tool for Checking Fluid Level and Filling Transmissions

A tool has just been released from Rotunda & other manufacturers (Fluid Transporter 307-D465) that can be used for filling or removing fluid from automatic or manual transmissions, axles, and power steering, quickly with no mess. This is in the 5R55N, 5R55S & 5R55W transmissions that have a Fluid Level & Fill Plug. Assembly in the bottom pan, and do not have a dipstick and filler tube.

Service Procedure

Transmission Fluid Level Check & Fill

1. Using the scan tool, monitor the transmission fluid temeperature (TFT) using the PID: TFT.
Desired fluid temp at the end of this procedure will be between 80-120°F (27-49°C).
2. Start the vehicle (Engine idle speed should be approximately 650 rpm).
3. Place the range selector lever in the PARK position.
4. With the engine running, position the vehicle on a hoist and set it as close to level as possible.
5. Hold the larger drain plug with a wrench and remove the small (center) fluid level-indicating plug using a 3/16-inch Allen key (Figure 1)
6. Install the special tool 307-437 (Fluid Level and Fill Plug Adapter) into the center of the larger drain plug in the pan (Figure 2).
7. Fill the Fluid Transporter with the clean Mercon® V automatic transmission fluid.
8. Hang the Fluid Transporter under the vehicle. Position it upright and close to the transmission.
9. Connect the open end of the fluid hose from the Fluid Transporter to the Fluid Level and Fill Plug Adapter at the bottom of the transmission fluid pan (Figure 3).
10. Apply air pressure (maximum of 30 psi) to the open end of the vacuum/pressure hose from the Fluid Transporter. Fluid will immediately start flowing out of the Fluid Transporter into the transmission fluid pan (Figure 4).
11. Add one pint of transmission fluid into the fluid pan. Stop the process by releasing the air pressure and removing the air nozzle from the end of the vacuum/pressure hose.
12. Inspect the fluid level in the Fluid Transporter canister. If the fluid drains back into the canister, the transmission is full. If no fluid drains back, more fluid will need to be added. Repeat steps 11 and 12.
13. Once the transmission is full, place a hand vacuum pump on the open end of the vacuum/pressure hose of the Fluid Transporter and apply vacuum to the system. This will pull out any extra fluid trapped in the system and direct it into the canister.
14. Allow the fluid to drain. Make sure that the fluid temperature is between 80-120°F (27-49°C).
15. Reinstall the small (center) fluid level indicating plug using a 3/16-inch Allen key.
16. Check the operation of the transmission by moving the range selector lever slowly through each gear, stopping in each position and allowing the transmission to engage.