P0734: Gear 4 Incorrect Ratio
22 vehicles · 6 makes · $100-$12,000 repair
Most Reported On
P0734 is an OBD-II diagnostic trouble code meaning “Gear 4 Incorrect Ratio.” The transmission is not achieving the correct gear ratio in 4th gear. This code is most commonly reported on 2007-2026 BMW X5, 2011-2026 BMW X3, and 2016-2021 BMW M2, plus 19 other vehicles, with repair costs ranging from $100 to $12,000.
Common Causes
Typical Repair Cost
Based on 26 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0734, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (22)
Transfer Case Actuator Motor Failure
Transfer Case Actuator Motor Failure
DCT (M-DCT) Mechatronics Unit Failure
Transfer Case Actuator Motor Failure
Transfer Case Failure - xDrive Models E84/F48 X1
Aisin 8-Speed Transmission Jerking
xDrive Transfer Case Stress & Fluid Degradation - F98 X4 M / F98 X4 M
xDrive Transfer Case Stress & Fluid Degradation - F97 X3 M / F98 X4 M
SMG Hydraulic Pump and Clutch Actuator Failure
Transfer Case Actuator Motor Failure (xDrive AWD System)
SMG III Hydraulic Pump Failure - E60 M5
DCT Dual-Clutch Transmission Shudder & Clutch Wear - F87 M2/M2C
xDrive Transfer Case Actuator Motor Failure - E70/F85/F95 X5 M
ZF 8HP Transmission Mechatronic Issues (All 8 Series & M8)
Transfer Case Actuator Motor Failure (All xDrive Models)
ZF 6HP Transmission Mechatronic Sleeve & Valve Body Failure
Automatic Transmission No-Reverse / Failsafe Due to ZF 5HP19 Drum and Valve Body Wear
DCT Dual-Clutch Transmission Wear & Judder - F10 M5
DCT Dual-Clutch Transmission Shudder & Clutch Wear - F82/F83 M4
SMG III Hydraulic Pump Failure (M6 and SMG-Equipped 645Ci/650i)
FAQ
What does P0734 mean?
P0734 stands for "Gear 4 Incorrect Ratio." The transmission is not achieving the correct gear ratio in 4th gear.
What are the most common causes of P0734?
The most common causes of P0734 are: Worn clutch pack, Valve body malfunction, Low fluid pressure, Failed accumulator, Internal seal leak. The specific cause varies by vehicle.
How much does it cost to fix P0734?
Repair costs for P0734 range from $100 to $12,000, depending on the vehicle and root cause.
Which vehicles are affected by P0734?
Au7o has documented P0734 across 22 vehicle models from 6 manufacturers: Acura, BMW, Chrysler, GMC, Hyundai, Kia.
Sources (12)
- media2007 Hyundai Veracruz Automatic Transmission Problems - CarComplaints
- ForumBimmerpost X1 Forum - Transfer case actuator gear / xDrive malfunction discussion
- NHTSANHTSA Vehicle Page for 2018 BMW X2 - Complaints and Investigations
- TSBBMW Technical Service Bulletin GBSEL-SELP24 - Transmission Jerking and Delayed Reverse Engagement
- ForumReddit r/BMW Discussion: 2018 BMW X2 Transmission Jerking Problem
- ForumBimmerpost X3M/X4M Forum - Transfer case fluid service interval discussion for F97/F98
- NHTSANHTSA Vehicle Page for 2007 BMW M6 - includes complaints and investigations related to SMG transmission issues
- videoYouTube Repair Video by 'BMW Repair Guide': Replacing SMG Hydraulic Pump on BMW M6 E63
- ForumXoutpost / X3 Forum - DIY Transfer Case Actuator Gear Replacement (BMW X3/X5/X6 xDrive)
- NHTSANHTSA Complaint #10406933 - 2006 BMW M5 transmission/SMG failure
- ForumBimmerpost F87 M2 Forum - DCT shudder / clutch slip discussion threads
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.