Technical Service Bulletins
|Publication Date: MARCH 16, 1998|
|1997-1998 EXPEDITION, F-150, F-250 LD|
This TSB article is being republished in its entirety to correct the parts listed.
The Malfunction Indicator Lamp (MIL) may illuminate and Diagnostic Trouble Code (DTC) P0503 may be stored in memory. There may also be transmission shift concerns and/or erratic speedometer operation. This may be caused by the speedometer drive gear being loose on the transfer case output shaft.
Replace the speedometer drive gear. The new gear has a tighter fit and should reduce the possibility of erratic signals. Refer to the following Service Procedure for details.
- Perform normal diagnostics as outlined in the 1997 or 1998 Powertrain Control/Emissions Diagnosis (PC/ED) On-Board Diagnostics II (OBDII) Service Manual. Service as required.
- If no concerns were found or the concern is still present, replace the speedometer drive gear.
- Remove the four (4) rear driveshaft flange bolts and remove the rear driveshaft.
NOTE: TO MAINTAIN INITIAL DRIVESHAFT BALANCE, MARK THE REAR DRIVESHAFT YOKE AND AXLE FLANGE SO THEY CAN BE REASSEMBLED IN THEIR ORIGINAL POSITIONS.
- Remove the six (6) extension housing bolts and remove the rear extension housing.
- Remove the speedometer gear spacer then push the speedometer drive gear toward the transfer case and remove the steel ball. The speedometer drive gear can now be removed from the output shaft.
- To install the revised Speedometer Drive Gear (F7TZ-17285-AA), reverse the removal procedure.
NOTE: THE NEW SPEEDOMETER DRIVE GEAR WILL HAVE A SLIGHT INTERFERENCE FIT, HOWEVER IT WILL GO ON TO THE OUTPUT SHAFT BY HAND. DO NOT HEAT THE GEAR.
- Before installing the extension housing, apply a small bead of sealant to the transfer case cover and extension housing mating surfaces. Use Ford Ultra Silicone Sealant (F7TZ-19554-AA or equivalent).
- Top off transfer case with MERCON® (XT-2-QDX).
|PART NUMBER||PART NAME|
|F7TZ-19554-AA||Ultra Silicone Sealant|
|F7TZ-17285-AA||Speedometer Drive Gear|
OTHER APPLICABLE ARTICLES:
Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage And Emissions Warranty Coverage
|980508A||Replace Speedometer Drive Gear||0.8 Hr.|
|BASIC PART NO.||CONDITION CODE|
204000, 204100, 204200, 206000, 501000, 501200, 502000, 508000, 698298