Shift Concern: Harsh 3-4 Shift

WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

SHIFT CONCERN: HARSH 3-4 SHIFT

Possible Component	Reference/Action
234 - ROUTINE
Powertrain Control System
PCM, vehicle wiring harnesses, shift control solenoid A, pressure control solenoids C, digital TR sensor, TFT sensor	Carry out On-Board Diagnostic Tests. See INTRODUCTION - GASOLINE article for diagnosis and testing of the PCM. GO to PINPOINT TEST A , GO to PINPOINT TEST B , GO to PINPOINT TEST C and GO to PINPOINT TEST D . Repair as required. Clear DTCs, road test and rerun On-Board Diagnostic Test.
Incorrect Pressures
High/low pressures	Check pressure at line and PC C taps. Carry out Line Pressure Test. Refer to SPECIAL TESTING PROCEDURES .
Main Control
Screws not tightened to specification	Tighten to specification.
Separator plate damaged	Inspect for damage. If damaged, install a new separator.
Contamination	Disassemble and clean.
Valve/springs damaged, misassembled, missing, stuck or bore damaged	If damaged or parts are missing, install new main control assembly. If misassembled, reassemble correctly. DO NOT stone, file or sand valves. This will remove the anodized finish and may result in further main control or transmission damage.
Filter damaged or missing	Inspect for damage. Repair as necessary.
Center Support
Screws not tightened to specification	Tighten to specification.
Seal rings or bearing damaged	Inspect for damage. Repair as necessary.
Outside diameter of case bore damaged	Inspect for damage. Repair as necessary.
Support damaged or leaking	Inspect for damage. Repair as necessary.
Direct Clutch Assembly
Seals, piston damaged	Inspect for damage. Repair as necessary.
Check ball damaged, missing, not seating, off location	Inspect for mislocation, poor seating, damage. Install a new cylinder.
Friction elements damaged or worn	Inspect for damage. Repair as necessary.
Return springs damaged	Inspect for damage. Repair as necessary.
Intermediate Servo
Seals (piston and cover) damaged	Inspect for damage. Repair as necessary.