P0734
7 owner reports and 478 manufacturer filings across 50 model years from Ford, Lincoln, Ram.
Where P0734 shows up
Source: NHTSA manufacturer communications and complaintsA model year appears here because the code is named in its record, not because every one of these vehicles sets it. Counts are mentions in the federal files, not failure rates — nobody publishes the denominator.
What it gets filed under
What owners said
Source: NHTSA complaint databaseOwners’ own words, one per nameplate, scrubbed of anything identifying. These are unverified reports filed with NHTSA — they are what was said, not a finding that it was true.
Performed IDS diag at shop, found hitorical code P0734 for "Incorrect gear 4 ratio" TSB 26-2046 to overhaul transmission
Only at this point did the vehicle display a warning: “Powertrain Malfunction / Reduced Power.� I scanned the vehicle and retrieved DTC P0734 – Gear 4 Incorrect Ratio, a code associated with internal transmission faults
The vehicle was taken to a dealer and DTC: P0734 (CDF Drum) was retrieved
2021 Ford Ranger with 10R80 transmission showing following codes P0733 P0734 90,000 miles on truck
Manufacturer filings that name it
Source: NHTSA manufacturer communicationsService bulletins and campaigns whose filed summary names P0734. Quoting the document number at a service desk is often the fastest route to a diagnosis someone has already written down.
- TSB 24-21762024-05-31 · Unknown Or Other
- This article supersedes TSBs 24-2100 and 24-2070 to add 2023 F-150 vehicles, update the TSB Issue statement and the TSB Service Procedure. Some 2021-2023 F-150, 2022-2023 Expedition/Navigator/Mustang and 2020-2023 Transit/Explorer/Aviator vehicles equipped with a 10R80/10R80MHT transmission may exhibit a harsh/delayed engagement and/or harsh/delayed shift, an illuminated malfunction indicator lamp
- TSB 24-20702024-03-13 · Power Train
- Some 2023 F-150 vehicles equipped with a 10R80/10R80 MHT transmission may exhibit a harsh/delayed engagement and/or harsh/delayed shift, an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTC) P0751, P0752, P0756, P0757, P0761, P0762, P0766, P0767, P0771, P0772, P2700, P2701, P2702, P2703, P2704, P2705, P2707, P2708, P0729, P0731, P0732, P0733, P0734, P0735, P0736, P076
- TSB 23-22502023-08-14 · Power Train
- This article supersedes TSB 22-2428 and 23-2176 to update the Issue, Action and Service Procedure. Some 2017-2023 F-150, 2018-2023 Expedition/Navigator/Mustang, 2019-2023 Ranger, 2020-2023 Explorer/Aviator/Transit and 2021-2023 Bronco vehicles equipped with a 10R60/10R80/10R80MHT transmission may exhibit a harsh/delayed engagement and/or harsh/delayed shift, an illuminated malfunction indicator la
- TSB 22-24282023-05-29 · Power Train
- Some 2017-2023 F-150, 2018-2023 Expedition/Navigator/Mustang, 2019-2023 Ranger, 2020-2023 Explorer/Aviator/Transit and 2021-2023 Bronco vehicles equipped with a 10R60 transmission and built on or before 23-Dec-2022 or with a 18R80/10R80MHT transmission and built on or before 15-Aug-2022 may exhibit a harsh/delayed engagement and/or harsh/delayed shift. It is possible the vehicle may also have an i
- TSB 23-21522023-05-23 · Power Train
- This article supersedes TSB 23-2123 to update the Issue statement. Some 2017-2020 F-150, 2018-2021 Expedition/Navigator/Mustang and 2019-2023 Ranger vehicles equipped with a 10R80 automatic transmission may exhibit a harsh engagement/harsh shift/delayed shift. It is possible the vehicle may also have an illuminated malfunction indicator lamp (MIL) or diagnostic trouble codes (DTC) P0751, P0752, P0
- TSB 23-21232023-04-14 · Power Train
- Some 2017-2020 F-150, 2018-2021 Expedition/Navigator/Mustang and 2019-2023 Ranger vehicles equipped with a 10R80 automatic transmission may exhibit a harsh engagement/harsh shift/delayed shift. It is possible the vehicle may also have an illuminated malfunction indicator lamp (MIL) or diagnostic trouble codes (DTC) P0751, P0752, P0756, P0757, P0761, P0762, P0766, P0767, P0771, P0772, P2700, P2701,
What P0734 means
Source: SAE J2012 / OBD-IIP0734 sits in the generic range of the OBD-II standard, so it means the same thing on every vehicle sold in the United States — but WhichTrim does not carry a definition for it and will not invent one. What is on this page is the record: who named it and on what.
A stored code names the test that failed, never the part that caused it. It is the starting point of a diagnosis, not its conclusion — the same code has several possible causes and the cheap one is not always right.
Common questions about P0734
Source: NHTSA files and the OBD-II standardCan I keep driving with P0734 stored?
Nobody can answer that from the code alone, and a site that does is guessing. A steady light generally means the fault was logged and the vehicle is in a reduced-risk mode; a flashing light means stop soon, because a misfiring engine can destroy a catalytic converter in minutes. The safe read of this page is the mileage and the components, not permission.
Does a code mean the car is recalled?
No. Recalls are filed by campaign and matched by VIN, and none of them are triggered by a scan tool. If you want to know whether an open recall applies to one specific vehicle, check the VIN at nhtsa.gov/recalls — that is the only source that settles it.
Why do the counts here differ from other sites?
Because these are not estimates. Every number on this page is a count of documents in NHTSA's own files: manufacturer communications that name the code in their filed summary, and owner complaints that name it in the narrative. We do not model, weight or extrapolate them.
Will clearing the code fix it?
Clearing turns the light off and erases the freeze-frame data a technician would have used to work out what happened. If the condition is still there the code returns, usually within a few drive cycles, and the diagnosis now starts from less information than before.