SECTION 308-03A: Manual Transaxle/Transmission — MT82 Getrag 6-Speed
2014 Mustang Workshop Manual
DIAGNOSIS AND TESTING
Procedure revision date: 06/20/2013

Manual Transmission

 

Inspection and Verification

NOTICE: If transmission noise is reported, first check the transmission fluid level. The vehicle should not be driven if the transmission fluid level is low. A low transmission fluid level will damage the transmission.

NOTE: If an observed or reported concern is found, correct the cause before proceeding.

Gear driven units produce a certain level of noise. Some noise is acceptable and audible at certain speeds or under various driving conditions. Many conditions, such as road and weather can amplify normal vehicle noise.

The following overview is a guide to diagnose a transmission or clutch concern:

Check Fluid Level and Condition

NOTICE: Excessive temperatures may break down the transmission lubricant. If there is reason to believe the transmission has been subjected to temperatures exceeding 135°C (275°F) for an extended period (greater than 20 minutes), change the lubricant immediately.

An incorrect transmission fluid level may affect the transmission operation and can result in transmission damage. For transmission draining and filling, refer to Transmission Draining and Filling .

A low transmission fluid level can result in poor transmission shifting, engagement or damage. It also indicates a leak in the transmission seals or gaskets.

  1. Check the transmission fluid condition.

Evaluate Clutch Hydraulic System

  1. Verify the clutch hydraulic fluid reservoir is filled to the correct level.

Evaluate the Clutch

  1. Apply and release the clutch pedal slowly to check pedal binding. Make sure the clutch pedal can be fully applied and is not restricted by the floor mat.
  1. With the engine idling and the park brake applied, move the gearshift lever into 4th gear. Increase engine speed to 2,000 rpm and slowly release the clutch pedal.

Inspect Gearshift Mechanism

  1. Inspect the gearshift mechanism for:
  1. Repair as necessary.

Evaluate Transmission

NOTICE: The vehicle should not be driven if the transmission fluid level is low or damage may occur.

NOTE: Before attempting to repair any concerns, road test the vehicle to determine which system the concern is in.

  1. Road test the vehicle. Use the following methods to diagnose the concern.
  1. The following list of conditions are typical clutch concerns. Refer to Section 308-01 .
  1. The following list of conditions are typical clutch hydraulic system concerns. Refer to Section 308-02 .
  1. Compare the road test results with the following symptom charts. The following list of conditions are typical transmission concerns:
    GO to Symptom Chart - Transmission Operation or GO to Symptom Chart - NVH .
 

Symptom Chart — Transmission Operation

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Diagnostic Methods in Section 100-00 for information about these practices.

 
Symptom Chart — Transmission Operation
Condition Possible Sources Action
  • Transmission difficult to shift
  • Lubricant
    • Internal shift mechanism
    • CHECK the internal shift mechanism for smooth operation. REPAIR or INSTALL a new mechanism as necessary.
      • Sliding gears, synchronizers
      • CHECK for free movement of gears and synchronizers. REPAIR or INSTALL new components as necessary.
        • Housings, shaft
        • CHECK for binding condition between the input shaft and the engine crankshaft pilot bearing or bushing. REPAIR or INSTALL new components as necessary. REFER to Section 308-01 .
          • Loose pressure plate to flywheel bolts
          • CHECK for loose bolts at the pressure plate. INSTALL new components as necessary. REFER to Section 308-01 .
          • Transmission will not shift — gearshift lever moves
          • Gearshift lever damaged
            • Damaged or worn selector arm. Loose shift rail bushings
            • CHECK the internal shift components. INSTALL new component as necessary.
              • Damaged or offset lever plate
              • CHECK the internal shift components. INSTALL new component as necessary.
              • NOTE: While verifying the condition, determine whether the noise is gear rollover noise, release bearing rub or some other transmission-related noise. Gear rollover noise, inherent in manual transmissions, is caused by the constant mesh of gears turning at the engine idle speed while the clutch is engaged and the transmission is in NEUTRAL. Release bearing rub is sometimes mistaken for mainshaft bearing noise. Gear rollover noise will disappear when the clutch is disengaged or when the transmission is engaged in gear. Release bearing rub will disappear when the clutch is engaged. In the event that a bearing is damaged, the noise is more pronounced while engaged in gear under load or coast than in NEUTRAL.
              • Noisy in forward gears

              • Lubricant
                • Components grounding out on the transmission
                • CHECK for screws and bolts of body or other components grounding out. CORRECT as necessary.
                  • Components housing bolts
                  • CHECK the torque on the transmission-to-flywheel housing bolts and the flywheel housing-to-engine block bolts. TIGHTEN the bolts to specification.
                    • Bearings or gears
                    • INSPECT the bearings. INSPECT the gears and gear teeth for wear or damage. INSTALL new components as necessary.
                      • Axle howl or whine
                      • The MT82 transmission may be suspect of a gear whine noise, which seems to be emanating from the rear of the vehicle at or in excess of 80 km/h (50 mph) at full operating temperature. Drive the vehicle at customer complaint speeds in 5th gear (this is the direct gear) to eliminate manual transmission as noise source, reach full operating temperature and confirm if noise is still present. Refer to Section 204-00 Symptom charts for "axle howling or whine" if noise is present. If not, proceed with gear noise analysis.
                      • Gears clash when shifting from one forward gear to another
                      • Pilot bearing
                      • CHECK for a binding condition between the input shaft and the engine crankshaft pilot bearing. INSTALL new components as necessary. REFER to Section 308-01 .
                        • Gear teeth and/or synchronizer
                        • REPAIR or INSTALL new components as necessary.
                          • Damaged shift forks or worn shift fork inserts
                          • INSPECT for wear or damage. INSTALL new components as necessary.
                          • Transmission jumps out of gear
                          • Transmission-to-engine mounting bolts
                          • TIGHTEN the bolts to specification.
                            • Crankshaft pilot bearing
                              • Internal damage
                              • INSPECT the synchronizer sleeves for free movement on their hubs. INSPECT the synchronizer blocking rings for widened index slots, rounded clutch teeth and smooth internal surface. CHECK shift forks for worn or loose mounting on shift rails. INSPECT the synchronizer sliding sleeve and the gear clutch teeth for wear or damage. REPAIR or INSTALL a new component as necessary.
                                • Gear teeth
                                • If worn or damaged, INSTALL new gears.
                                • Transmission will not shift into one gear — all others OK
                                • Manual shift linkage
                                • REPAIR or INSTALL new components as necessary.
                                  • Backup switch ball
                                  • If REVERSE is the problem, CHECK reverse lamp switch for ball frozen in extended position.
                                    • Internal components
                                    • INSPECT the shift rail and fork system, synchronizer system and the gear clutch teeth for restricted travel. REPAIR or INSTALL new components as necessary.
                                    • Transmission is locked in one gear and cannot be shifted out of that gear
                                    • Internal components
                                    • INSPECT the problem gears, shift rails, forks and the synchronizer for wear or damage. REPAIR as necessary.
                                      • Fork on rail or shift rail
                                      • CHECK the shift rail interlock system. REPAIR as necessary.
                                      • Transmission leaks
                                      • Lubricant
                                      • CHECK the level and type.
                                        • Other component leaking
                                        • IDENTIFY leaking fluid as engine, power steering or transmission fluid. REPAIR as necessary.
                                          • False report
                                          • REMOVE all traces of lube on the exposed transmission surfaces. CHECK the vent for free breathing. OPERATE the transmission and INSPECT for new leakage. REPAIR as necessary.
                                            • Internal components
                                            • INSPECT for leaks at the input shaft seal. INSPECT the case for sand holes or cracks. REPAIR or INSTALL a new case as necessary.
                                              • Fill and drain plugs
                                              • CHECK fill and drain plugs and bore threads. REPAIR as necessary. TIGHTEN plugs to specified torque value.
                                              • Bearing failure
                                              • Other part failure
                                              • Raceways or rollers
                                              • Lubricant
                                              • Towing vehicle further than 80 km (50 mi) with driveshaft installed.
                                              • REMOVE, DISASSEMBLE and CLEAN the transmission. Inspect for damaged parts and install new components as necessary. (Note: RESET the bearing preload if any new tapered bearings are installed.).
                                                • Vibration break-up of retainer and brinelling of races
                                                • Bearing(s)
                                                • Shafts or bore
                                                • Overloading of vehicle
                                                • Incorrect preload
                                                • DETERMINE the cause of vibration and CORRECT. Otherwise, PROCEED as above.
                                                  • Input shaft oil dam
                                                  • INSTALL new components as necessary and VERIFY the oil dam installation is correct. CHECK for correct installation of the snap ring on the mainshaft next to the oil dam.
                                                    • Oil baffle in the input bearing shim pack
                                                    • INSTALL a new oil baffle, making sure it is not damaged during assembly.
                                                     

                                                    Symptom Chart — NVH

                                                    Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Diagnostic Methods in Section 100-00 for information about these practices.

                                                     
                                                    Symptom Chart — NVH

                                                    NOTE: NVH symptoms should be identified using the diagnostic tools that are available. For a list of these tools, an explanation of their uses and a glossary of common terms, refer to Section 100-04 . Since it is possible any one of multiple systems may be the cause of a symptom, it may be necessary to use a process of elimination type of diagnostic approach to pinpoint the responsible system. If this is not the causal system for the symptom, refer back to Section 100-04 for the next likely system and continue diagnosis.

                                                    Condition Possible Sources Action
                                                    • Transmission rattle noise — noise occurs at 1st and 2nd gear on light acceleration.
                                                    • Gear engagement
                                                    • Acceptable operating condition. Caused by the contact pattern of these gears.
                                                    • Transmission rattling/clattering noise — occurs in NEUTRAL or in gear, at idle
                                                    • Incorrect fluid level or fluid quality
                                                    • Transmission rattling/clattering noise — noise at idle in NEUTRAL
                                                    • Worn or rough reverse idler gear
                                                    • CHECK the reverse idler gear. REPAIR as necessary.
                                                      • Excessive backlash in gears
                                                      • CHECK the gear backlash. ADJUST as necessary.
                                                        • Worn countershaft gears
                                                        • REPAIR as necessary.
                                                        • Transmission whine — a mild whine at extreme speeds or high rpm
                                                        • Rotating gears/geartrain
                                                        • Acceptable noise.
                                                        • Transmission whine — a high pitched whine, also described as a squeal
                                                        • Transmission gears are worn (high mileage vehicle)
                                                        • Result of normal gear wear. REPAIR as necessary.
                                                          • Mismatched gear sets
                                                          • INSPECT the gear sets for an uneven wear pattern on the face of the gear teeth. REPAIR as necessary.
                                                            • Damaged or worn transmission bearing
                                                            • INSPECT the transmission bearings. INSTALL new bearings as necessary.
                                                            • Transmission growling/humming — noise occurs in the forward gears. The noise is more prominent when the gear is loaded. The problem gear can be located as the noise occurs in a specific gear position
                                                            • Gear is cracked, chipped or rough
                                                            • INSPECT the transmission gears for damage or wear. INSTALL new gears as necessary.
                                                              • Axle howl or whine
                                                              • The MT82 transmission may be suspect of a gear whine noise, which seems to be emanating from the rear of the vehicle at or in excess of 80 km/h (50 mph) at full operating temperature. Drive the vehicle at customer complaint speeds in 5th gear (this is the direct gear) to eliminate manual transmission as noise source, reach full operating temperature and confirm if noise is still present. Refer to Section 204-00 Symptom charts for "axle howling or whine" if noise is present. If not, proceed with gear noise analysis.
                                                              • Transmission hissing — noise in NEUTRAL or in forward gears. As bearings wear or break up, the noise changes to a thumping noise
                                                              • Damaged or worn bearings
                                                              • INSPECT the transmission bearings. INSTALL new bearings as necessary.
                                                              • Transmission knocking/thudding — noise at low speeds in forward gears
                                                              • Bearings with damaged balls or rollers or with pitted and spalled races
                                                              • INSPECT the transmission bearings. INSTALL new bearings as necessary.
                                                              • Transmission rumble/growl — noise at higher speeds in forward gears, more pronounced in a coast/deceleration condition
                                                              • Incorrect driveline angle
                                                                • Driveshaft out of balance or damaged
                                                                • CHECK the driveshaft for damage, missing balance weights or undercoating. REFER to the driveshaft runout and balance test in Section 205-00 .
                                                                  • Axle howl or whine
                                                                  • The MT82 transmission may be suspect of a gear whine noise, which seems to be emanating from the rear of the vehicle at or in excess of 80 km/h (50 mph) at full operating temperature. Drive the vehicle at customer complaint speeds in 5th gear (this is the direct gear) to eliminate manual transmission as noise source, reach full operating temperature and confirm if noise is still present. Refer to Section 204-00 Symptom charts for "axle howling or whine" if noise is present. If not, proceed with gear noise analysis.
                                                                  • Transmission rumble/growl — noise at all speeds in forward gears, more pronounced in a heavy acceleration condition
                                                                  • Damaged or worn transmission bearing or gears (high mileage vehicles)
                                                                  • CHECK transmission fluid for excessive metal particles. REPAIR as necessary.