Symptom hub
High Highway RPM: Missing Overdrive, No Lockup, or Transmission Slip?
If engine RPM stays unusually high at steady cruise, the useful split is between missing converter lockup, a transmission that never reaches top gear, and real slip that keeps the ratio or lockup from stabilizing.
Likely related codes
Start your diagnostic path here
P0700 — Transmission Control System Malfunction P0730 — Incorrect Gear Ratio P0734 — Gear 4 Incorrect Ratio P0735 — Gear 5 Incorrect Ratio P0741 — Torque Converter Clutch Circuit Performance or Stuck Off P0740 — Torque Converter Clutch Circuit Malfunction P0743 — Torque Converter Clutch Solenoid Circuit Electrical P2714 — Pressure Control Solenoid D Performance or Stuck Off P2716 — Pressure Control Solenoid D Electrical P2761 — Torque Converter Clutch Pressure Control Solenoid Control Circuit/Open