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2002 FORD EXPLORER
4.0L V6 SOHC•4WD•AUTOMATIC•gas
10 active safety recalls on this vehicle — view recalls
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Repairs0Labor1011Torque10570Fluid18DTC1870Battery2Maintenance0Recalls10
P0731high severityPowertrain

Gear 1 Incorrect Ratio

on 2002 Ford Explorer 4.0L V6 SOHC · 4WD

What this code means

Incorrect gear ratio detected in 1st gear.

Symptoms

  • Slipping in 1st gear
  • Harsh 1-2 shift
  • No 1st gear

Common causes

  • 1st gear clutch pack worn
  • Shift solenoid issue
  • Valve body problem
  • Low line pressure

Diagnostic steps

  1. Check fluid
  2. Test shift solenoids
  3. Monitor gear ratio in 1st
  4. Check line pressure

Repair notes

Internal transmission service may be needed.

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Other Powertrain codes on this vehicle

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🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
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