Section 07-03: Transmission, Manual—T5OD
1994 Mustang Workshop Manual
DIAGNOSIS AND TESTING

Symptom Chart: Transmission Diagnosis

SYMPTOM CHART: TRANSMISSION DIAGNOSIS
ConditionPossible SourceAction
  • Transmission Noisy in Gear
  • Lubricant level low or wrong type.
  • Fill to bottom of filler plug hold with proper lubricant.
 
  • Transmission to flywheel housing and flywheel housing to engine block bolts loose.
  • Tighten bolts to 61-88 Nm (45-65 lb-ft).
 
  • Pilot mainshaft bearing roller worn or damaged.
  • Remove transmission . If noise is howling during start-up, check pilot mainshaft bearing roller . Check for loose flywheel and flywheel housing alignment. Service or replace as required. Refer to Section 08-00.
 
  • Improper transmission pilot engagement into flywheel housing .
  • Replace housing or main drive gear bearing retainer as required. Refer to Section 08-00.
 
  • Worn or damaged internal components.
  • Disassemble transmission. Inspect input input shaft and extension housing seal , output and countershaft bearings , gear and gear teeth for wear and damage. Service or replace as required.
  • Transmission Leaks
  • Excessive amount of lubricant in transmission —wrong type.
  • Check level and type. Fill bottom of filler plug hole.
 
  • Other component(s) leaking.
  • Identify leaking fluid at engine, power steering pump and/or transmission .
 
  • False report.
  • Remove all traces of lubricant on exposed transmission surfaces. Check vent for free breathing. Operate transmission and inspect for new leakage. Service as required.
 
  • Worn or damaged internal components.
  • Remove transmission . Inspect for leaks at the input shaft and extension housing seal main drive gear bearing retainer , shift rail expansion plug top cover gasket. Inspect case for sand holes. Service or replace as required.
 
  • Inadequate thread sealant on threads.
  • Apply sealant to bolt threads.
 
  • Check rear yoke for burrs.
  • Service or replace as required.
  • Transmission Shifts Hard
  • Improper clutch release.
 
  • Internal shift mechanism binding.
  • Remove transmission and free up shift mechanism.
 
  • Synchronizer to hub fit.
  • Remove and check for burrs or fit.
 
  • Binding condition between input shaft and crankshaft mainshaft bearing roller .
  • Check alignment and service as required. Refer to Section 08-00.
 
  • Improper fluid.
  • Drain and refill with Synthetic MERCON® Multi-Purpose Automatic Transmission Fluid E6AZ-19582-B (ESR-M2C163-A2) or equivalent to bottom of filler plug hole.
  • Gears Clash When Shifting from One Forward Gear to Another
  • Engine idle speed too high.
  • Adjust engine idle speed.
 
  • Improper clutch release.
 
  • Binding condition between input shaft and crankshaft pilot mainshaft bearing roller .
  • Remove transmission and replace pilot mainshaft bearing roller (Section 08-00).
 
  • Worn or damaged gear shifter forks , synchronizer assembly, or gear clutch teeth.
  • Service or replace as required.
  • Transmission Jumps Out of Gear
  • Floor shift—stiff or improperly installed gearshift lever boot .
  • Verify jump-out with gearshift lever boot removed. Replace gearshift lever boot if necessary.
 
  • Floor shift—interference between shift handle and console panel .
  • Adjust console panel to eliminate interference.
 
  • Transmission to engine mounting loose.
  • Tighten bolts to specification.
 
  • Flywheel housing to engine crankshaft out of alignment.
  • Improper engagement between transmission pilot and flywheel housing .
 
  • Clutch release hub and bearing worn.
  • Replace clutch release hub and bearing . Refer to Section 08-00.
 
  • Worn or damaged internal components.
  • Check input shaft and output and fifth gear drive shaft for excessive end play, gear shifter forks for loose mounting on shift rails; worn pads, shift rail detent system for wear or damage; synchronizer sliding sleeve and gear clutch teeth for wear or damage. Service or replace as required.
  • Transmission Will Not Shift Into One Gear— All Other Gears OK
  • Floor shift, interference between shift handle and console panel or floor cut-out.
  • Adjust console panel or cut-out front floor pan to eliminate interference.
 
  • Restricted travel of internal shifter components.
  • Remove transmission . Inspect shift rail and fork system, synchronizer system and gear clutch teeth for restricted travel. Service and replace as required.
  • Transmission is Locked in One Gear. It Cannot be Shifted Out of that Gear
  • Internal shifter components worn or damaged.
  • Remove transmission . Inspect the problem gear or gearshift rails and fork and synchronizer for wear or damage. Service or replace as required.
 
  • Gear shift selector arm plate finger broken.
  • Remove transmission . Replace gear shift selector arm plate assembly.
 
  • Bent gear shifter forks at pads and selector slot.
  • Service or replace as required.
  • Transmission Will Not Shift Into Reverse (All Others OK)
  • Worn or damaged internal components.
  • Remove transmission . Check for damaged reverse geartrain, misaligned reverse relay lever, shift rail and fork system. Service or replace as required.