What Does P073B Mean?
The TCM has detected that the transmission is stuck in 6th gear and cannot shift to any other gear. The 6th gear clutch elements remain engaged regardless of driving conditions or TCM commands. The driver will experience extremely poor acceleration from a stop, the engine lugging severely or stalling at low speeds, and only comfortable operation at sustained highway speeds.
Safety Warning
6th gear is the highest overdrive ratio — starting from a stop in 6th gear is virtually impossible without stalling. The vehicle is undrivable in city conditions. Have the vehicle towed. If already on a highway at speed, maintain speed and proceed directly to a repair facility without stopping if possible.
Common Causes
35%
TCM has entered limp/failsafe mode in 6th gear due to an underlying critical transmission or sensor fault
25%
Failed shift solenoid(s) preventing the transmission from leaving 6th gear
20%
Stuck valve(s) in the valve body maintaining 6th gear hydraulic circuit engagement
10%
6th gear clutch pack mechanically bonded or stuck in the applied position
10%
Faulty speed sensors providing incorrect data that prevents the TCM from commanding other gears
Diagnostic Steps
1
Scan for all DTCs in the TCM, ECM, and other modules — 6th gear default is a limp mode condition triggered by another underlying fault.
2
Confirm the stuck-in-6th condition by calculating gear ratio from ISS/OSS PIDs and verifying it matches the 6th gear specification across all driving conditions.
3
Attempt to command gear changes via scan tool bi-directional controls. Note which gears respond and which do not to narrow down the fault.
4
Test the shift solenoids individually — measure resistance, current draw, and operation. Reference the solenoid application chart to identify which solenoid(s) should release 6th gear.
5
If solenoid tests pass, remove the valve body and inspect the relevant shift valves for scoring, varnish buildup, or mechanical binding that prevents them from repositioning.
Estimated Repair Cost
$200 - $4,000
Parts + labor, varies by vehicle and location
The TCM has detected that the transmission is stuck in 6th gear and cannot shift to any other gear. The 6th gear clutch elements remain engaged regardless of driving conditions or TCM commands. The driver will experience extremely poor acceleration from a stop, the engine lugging severely or stallin...
The most common cause of P073B (Stuck in Gear 6) is: TCM has entered limp/failsafe mode in 6th gear due to an underlying critical transmission or sensor fault
Typical repair costs for P073B range from $200 to $4,000, depending on the vehicle, location, and whether you do it yourself or go to a shop.
6th gear is the highest overdrive ratio — starting from a stop in 6th gear is virtually impossible without stalling. The vehicle is undrivable in city conditions. Have the vehicle towed. If already on a highway at speed, maintain speed and proceed directly to a repair facility without stopping if possible.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P073B to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Automatic Transmission / Gear Engagement
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
