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99-16-10 TRANSMISSION - 4R44E OR 5R55E - SLIPPING SHIFT/DELAYED OR NO ENGAGEMENT
Publication Date: AUGUST 2, 1999
FORD: 1999 EXPLORER, RANGER
MERCURY: 1999 MOUNTAINEER
ISSUE:
Slipping transmission shifts and/or delayed or no transmission engagements may occur on some vehicles. The Electronic Pressure Control (EPC) solenoid may cause stress on the attaching bracket. This stress causes the bracket to break and the EPC solenoid to back out of its bore causing line pressure to drop too low or fluctuate, allowing friction clutches to slip.
ACTION:
Diagnose and inspect for damaged EPC attachment bracket, and replace the bracket and EPC solenoid with new bracket and revised EPC solenoid. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
Perform normal diagnosis for this concern.
Perform Line Pressure Tests as listed in the 1999 Explorer/Mountaineer, Ranger Workshop Manual.
If pressures are low, perform Pinpoint Test for the EPC solenoid.
Inspect the bracket that attaches the Torque Converter Clutch (TCC), Shift Solenoid B (SSB), Shift Solenoid D/Coast Clutch Solenoid (SSD/CCS), and EPC solenoids to the main control for damage. If the bracket is damaged, replace both the bracket and solenoid.
If the bracket is not damaged, inspect the solenoid for the affected date code (refer to the following Manufacturing Date Code Chart) and ID marking (Figure 1, Views 1, 2, and 3). If the solenoid is one of the affected, replace it.
MANUFACTURING DATE CODE
Date Code Month/Year
868xx August 1998
869xx September 1998
870xx October 1998
871xx November 1998
872xx December 1998
Inspect the fluid pan for major contamination.
If contamination is minimal, clean the main control, but do not replace.
If major contamination is present, perform normal transmission overhaul as required, including main control replacement. Pay particular attention to the condition of the friction plates. Repair as required.
After repairs are completed, verify concern has been fixed.
PART NUMBER PART NAME
F87Z-7A100-AB Main Control (2.5L Ranger 4X2)
F87Z-7A100-BB Main Control (3.0L Ranger)
F87Z-7A100-CB Main Control (4.0L Ranger)
F87Z-7A100-DB Main Control (4.0L EI Explorer)
F87Z-7A100-EB Main Control (4.0L SOHC Explorer)
XL2Z-7L491-AA Bracket
XL2Z-7G383-AA Electronic Pressure Control (EPC) Solenoid
OTHER APPLICABLE ARTICLES:
NONE
WARRANTY STATUS:
Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage And Emissions Warranty Coverage
OPERATION DESCRIPTION TIME
991610A Replace Electronic Pressure Control (EPC) Solenoid And Clean Main Control (Includes Time For Road Test) - 4R44E Or 5R55E 1.2 Hrs.
991610B For Line Pressure And Pinpoint Tests, Use "A" Time As Outlined In The Warranty And Policy Manual
DEALER CODING
BASIC PART NO. CONDITION CODE
7G383 01
OASIS CODES:
501000, 502000, 503000
Figure 1 - Article 99-16-10
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Copyright © 1999 Ford Motor Company
