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2003 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas•3RZ-FE
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1066Torque2197Fluid17DTC3480Battery2Maintenance0Recalls5
P0783moderate severityPowertrain

3-4 Shift Malfunction

on 2003 Toyota Tacoma 2.7L I4 · RWD

What this code means

The transmission failed to complete the shift from 3rd to 4th gear within the expected time or range. This usually points to a hydraulic or solenoid issue in the shift circuit.

Symptoms

  • No 3-4 upshift
  • Harsh or delayed shifting
  • Check engine light on

Common causes

  • Faulty shift solenoid
  • Low or dirty transmission fluid
  • Worn valve body
  • Internal transmission wear

Diagnostic steps

  1. Check transmission fluid level and condition
  2. Scan for related transmission codes
  3. Test shift solenoid operation and resistance
  4. Inspect valve body and hydraulic circuits
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Other Powertrain codes on this vehicle

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