Select-o-Speed Trans Problems

Ford Tractor Select-O-Speed Troubleshooting 1959-1962 Overrunning clutch models

Malfunction – Common

CausesTransmission remains in Park

  • Low fluid pressure
  • Bands 2 and/or 3 not released
  • Damaged or broken selector cable

Transmission goes to Neutral

  • Band 2 or 3 not released
  • Clutch packs not engaged
  • Traction coupling disengaged
  • Damaged or broken selector cable

Transmission functions in all selector positions, but can be held in tenth speed without stalling the engine (1500 rpm) when brakes are applied

  • Low fluid pressure
  • Defective torque limiting clutch

Transmission functions in reverse only

  • Mainshaft broken or damaged spline on “B” carrier

Transmission functions in 3, 4, 7, 8, 10, and R2 only

  • Overrunning clutch not applying

Transmission functions in all selector positions but provides the direct ratios only

  • Band 1 not applying

Transmission goes to Neutral in Park, 5, 6, 7 and 8

  • Band 2 not applying

Transmission goes to Neutral in Park, 1, 2, 3, 4, R1 and R2

  • Band 3 not applying

Transmission goes to Neutral in 9, 10, R1 and R2

  • Clutch 1 not applying

Transmission goes to Neutral in 2, 4, 6, 8, 9 and 10

  • Clutch 2 not applying

Transmission goes to Neutral in 1, 3, 5 and 7

  • Clutch 3 not applying

Transmission locks up in 3, 4, 7, 8, 10 and R2

  • Overrunning clutch not releasing

Transmission functions in all selector positions but provides the overdrive ratios only

  • Band 1 not releasing

Transmission locks up in 1, 2, 3, 4, 9, 10, R1 and R2, and goes to Park in Neutral

  • Band 2 not releasing

Transmission locks up in 5, 6, 7, 8, 9 and 10

  • Band 3 not releasing

Transmission locks up in Park, 1, 2, 3, 4, 5, 6, 7 and 8 and goes to R1 in Neutral

  • Clutch 1 not releasing

Transmission locks up in Park, 1, 3, 5, 7, R1 and R2 and goes to 2 in Neutral

  • Clutch 2 not releasing

Transmission locks up in Park, 2, 4, 6, 8, 9, 10, R1 and R2 and goes to 1 in Neutral

  • Clutch 3 not releasing

Root Causes

Low pump fluid pressure

  1. Low fluid level
  2. Plugged or incorrectly installed suction screen
  3. Pump gasket leaking
  4. Pump pressure line or “O” ring leaking
  5. Defective torque limiting clutch
  6. Defective pump
  7. Leakage between valve body halves
  8. Leaking valve body gasket
  9. System relief valve stuck open
  10. Restricted pressure line

Overrunning clutch inoperative (does not apply or release)

  1. Defective unit

Band 1 not applying

  1. Band too loose- adjust
  2. Band strut out
  3. Leakage between valve body halves
  4. Leaking valve body gasket
  5. Pressure line leaking
  6. Leaking servo “O” rings
  7. Scoring or burring of servo

Band 1 not releasing

  1. Band too tight- adjust
  2. Servo return spring broken or defective
  3. Band spool valve stuck
  4. Scoring or burring of servo

Band 2 or 3 not applying

  1. Band too loose- adjust
  2. Band strut out
  3. Servo spring broken or defective
  4. Scoring or burring of servo
  5. Servo spool valve stuck

Band 2 or 3 not releasing

Band too tight- adjust
Leaking valve body gasket
Leakage between valve body halves
Fluid line “O” rings leaking
Leaking servo seals
Scoring or burring of servo

Clutch 1 not applying

  1. Leaking valve body gasket
  2. Leaking piston “O” rings
  3. Mainshaft seals
  4. “C” sun gear seals
  5. Distributor seals
  6. Scored or burred piston

Clutch 1 not releasing

  1. Clutch spool valve stuck
  2. Scored or burred piston
  3. Broken or defective clutch spring
  4. Warped or defective clutch discs

Clutch 2 or 3 not applying

  1. Leaking valve body gasket
  2. Leaking piston “O” rings
  3. Mainshaft seals
  4. “C” sun gear seals
  5. Mainshaft core loose
  6. Broken mainshaft
  7. Leakage between valve body halves
  8. Scored or burred piston

Clutch 2 or 3 not releasing

  1. Clutch spool valve stuck
  2. Scored or burred piston
  3. Broken or defective clutch spring
  4. Warped or defective clutch plates

Thanks to John Smith of Old Ford Tractor for allowing us to use this information.