P0729 on Lincoln
Gear 6 Incorrect Ratio
P0729 on Lincoln vehicles indicates gear 6 incorrect ratio. Au7o has documented this code across 1 Lincoln model — most commonly on Aviator. P0729 means the transmission control system detected an incorrect gear ratio in 6th gear — the computer compares input shaft speed to output shaft speed and found the resulting ratio doesn't match what 6th gear should produce. This usually indicates the transmission is slipping in that gear, a clutch or band isn't holding, or a hydraulic/solenoid control problem is preventing proper engagement. You may feel slipping, flaring RPM, harsh shifts, or the transmission dropping into limp mode. Low fluid and worn internal components are frequent contributors. Typical repair costs on Lincoln range from $800 to $7,000, depending on the specific model and root cause.
Common Causes of P0729
- •Low or contaminated transmission fluid
- •Worn or slipping clutches/bands inside the transmission
- •Faulty shift solenoid or pressure control solenoid
- •Valve body wear or sticking valves
- •Failing torque converter
- •Internal mechanical wear or damage
- •Speed sensor fault giving incorrect ratio calculation
P0729 on Lincoln by Model
Lincoln Aviator(1 issue)
- 10R60/10R80 MHT Harsh/Delayed Shifts from Sticking Valve Body and CDF Clutch Sleeve Movement2020-2023
Many 2020-2023 Aviators with the 10R60 10-speed automatic (3.0L EcoBoost) and 10R80 MHT (Grand Touring PHEV) exhibit harsh 1-2/2-3 upshifts, clunky engagements into Drive or Reverse, and delayed shifts, with or without illuminated MIL. Root cause per Ford TSB 23-2250 is software/solenoid ID strategy, sticking valves in the main control valve body, and/or axial movement of the CDF clutch cylinder sleeve. Ford issued multiple TSBs (21-2316, 22-2102, 22-2428, 23-2250, 24-2046) and a related 10R80 class action is active in 2025 for sibling Ford/Lincoln models.
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What does P0729 mean on Lincoln?▼
P0729 stands for "Gear 6 Incorrect Ratio." P0729 means the transmission control system detected an incorrect gear ratio in 6th gear — the computer compares input shaft speed to output shaft speed and found the resulting ratio doesn't match what 6th gear should produce. This usually indicates the transmission is slipping in that gear, a clutch or band isn't holding, or a hydraulic/solenoid control problem is preventing proper engagement. You may feel slipping, flaring RPM, harsh shifts, or the transmission dropping into limp mode. Low fluid and worn internal components are frequent contributors. On Lincoln specifically, this code is documented across 1 model.
What causes P0729 on Lincoln vehicles?▼
Common causes on Lincoln: Low or contaminated transmission fluid, Worn or slipping clutches/bands inside the transmission, Faulty shift solenoid or pressure control solenoid, Valve body wear or sticking valves, Failing torque converter. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0729 on a Lincoln?▼
Repair costs on Lincoln range from $800 to $7,000, depending on the specific model and root cause.
Which Lincoln models have P0729 documented?▼
Au7o has documented P0729 on 1 Lincoln model: Aviator.