P0740 on Subaru: How to Diagnose & Fix
Torque Converter Clutch Circuit Malfunction
6 Subaru models · 7 documented issues · 6 critical · $200-$9,000 repair
P0740 on Subaru by model: symptoms, diagnosis and fix
The Lineartronic CVT (TR690) in 2014-2021 Foresters can develop shuddering, hesitation, and in severe cases, complete failure. Symptoms typically begin around 60,000-100,000 miles. The CVT chain can stretch, causing slippage and shudder during light acceleration. The torque converter can also develop issues. Subaru extended CVT warranty to 10 years/100,000 miles under Customer Satisfaction Program WTY-72. Multiple software updates have been released to address shifting behavior.
Common Symptoms
- Shuddering during light acceleration at 15-40 mph
- Hesitation or delay when accelerating from a stop
- CVT whining or droning noise
- Rough engagement into Drive or Reverse
- Transmission warning light on dashboard
How to Fix
Have the dealer check for and apply the latest CVT software updates (TSB 16-103-17R). Perform CVT fluid change with Subaru CVT Fluid Lineartronic II (SOA427V1700). If shuddering persists, torque converter replacement or complete CVT replacement may be needed. Verify coverage under Subaru's 10-year/100,000-mile CVT warranty extension.
The Lineartronic CVT can develop shudder, hesitation, or jerky operation, especially during light acceleration at low speeds. Subaru has updated CVT software multiple times to address these concerns.
Common Symptoms
- Shudder during light acceleration
- Hesitation from stop
- Jerky operation at low speeds
- CVT whine or noise
- Delayed engagement
How to Fix
Have dealer update CVT software to latest version. CVT fluid change may help. In severe cases, valve body or CVT replacement may be needed. Subaru extended CVT warranty on some vehicles.
Owner tips & cautions
- TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes
- TipSearch Subaru Outback forums and owner groups for real-world experiences and DIY guides
- TipGet multiple quotes from independent mechanics - dealer prices can be 2-3x higher for the same repair
The Ascent's high-torque Lineartronic CVT (TR730 - the largest CVT Subaru has produced) paired with the 2.4L turbo FA24 engine exhibits hesitation from stops, harsh engagement when shifting from Park to Drive/Reverse, and surging at low speeds. The TR730 CVT must handle significantly more torque than Subaru's other CVTs, leading to durability concerns. Multiple TSBs have addressed calibration issues. Some owners report complete CVT failure under 60,000 miles.
Common Symptoms
- 1-2 second hesitation when accelerating from a stop
- Harsh thunk when shifting from Park to Drive or Reverse
- Surging or bucking at low speeds in parking lots
- Shuddering during light acceleration at 25-40 mph
- Transmission warning light
- Burning smell from transmission area
How to Fix
Have dealer apply latest TCM software calibration (multiple TSBs released). Perform CVT fluid drain and refill with Subaru High Torque CVT Fluid (SOA427V1660) - note this is different from the standard CVT fluid. If hesitation persists after software update, valve body replacement may be needed. For complete failure, Subaru reman CVT is available. All Ascents have 10-year/100,000-mile CVT warranty from factory.
Sources for this issue (1)
The Ascent's TR730 high-torque CVT develops valve body failures that cause erratic shifting, harsh engagement, and transmission warning lights. The valve body controls hydraulic pressure to the CVT pulleys and chain, and when solenoids or passages within it fail, the transmission cannot maintain proper ratio control. This issue is distinct from the CVT hesitation TSB and represents a hardware failure rather than a calibration issue.
Common Symptoms
- Transmission warning light illuminated
- Harsh thud when shifting from Park to Drive
- CVT slipping or flaring RPMs under load
- Shuddering at highway speeds
- Vehicle going into limp mode (limited to low speeds)
- Burning fluid smell
How to Fix
Diagnose with dealer scan tool to confirm valve body solenoid fault codes. Valve body replacement resolves the issue in most cases — this is a less expensive repair than full CVT replacement. If the CVT has been operated with a failed valve body for an extended period, internal damage may necessitate full CVT replacement. Covered under Subaru's 10-year/100,000-mile CVT warranty.
Sources for this issue (4)
The Lineartronic CVT (TR690) used in Crosstreks develops chain stretch over time, typically between 80,000-130,000 miles. The stretched chain causes slippage, resulting in judder during light acceleration, particularly between 20-45 mph. The issue worsens in cold weather and uphill conditions. Subaru addressed earlier models under warranty extension WTY-72 (10 years/100,000 miles) and released multiple software calibration updates. In severe cases, the CVT requires complete replacement.
Common Symptoms
- Juddering or shaking during light acceleration at 20-45 mph
- Slipping sensation when climbing hills
- Delayed response when pressing accelerator
- Whining noise from transmission that increases with speed
- Check Engine Light with CVT-related codes (P0700, P2764)
How to Fix
Start with CVT fluid drain and refill using Subaru CVT Fluid Lineartronic II (SOA427V1700). Have dealer apply latest transmission control module software update. If judder persists, valve body replacement may resolve the issue. For severe chain stretch, full CVT replacement is needed (Subaru reman unit available). Verify if covered under Subaru's CVT warranty extension program WTY-72.
Sources for this issue (4)
The 2010+ Legacy uses the Lineartronic CVT (TR690 for 2.5L, TR580 for 2.5i base) which has widespread reports of premature failure, typically between 80,000-140,000 miles. Failures include chain stretch, torque converter shudder, valve body malfunction, and complete transmission failure. The 2010-2014 models are most affected. Subaru extended CVT warranty coverage to 10 years/100,000 miles. Symptoms often start with subtle judder during light acceleration and progress to complete loss of drive.
Common Symptoms
- Shudder during light throttle acceleration
- Delayed engagement when shifting from Park
- Loud whining from transmission area
- Loss of power under acceleration
- Transmission overheating warning
- Complete loss of forward or reverse gear
How to Fix
Perform CVT fluid exchange with Subaru Lineartronic CVT Fluid II. Apply latest TCM software calibration at dealer. For torque converter shudder, converter replacement ($1,500-2,500) is often sufficient. Full CVT replacement with Subaru remanufactured unit for complete failures. Check 10-year/100,000-mile warranty extension eligibility first.
Sources for this issue (3)
P0740 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0740 mean on a Subaru?
P0740 stands for "Torque Converter Clutch Circuit Malfunction." This code indicates a malfunction in the torque converter clutch (TCC) circuit of an automatic transmission. The torque converter clutch mechanically locks the engine to the transmission at cruising speed to improve fuel economy and reduce slippage, and it is engaged by a solenoid controlled by the transmission computer. The code sets when the computer detects an electrical problem with the clutch circuit or sees that the clutch is not engaging or holding as expected. Common signs include slipping, shuddering, poor fuel economy, or stalling when coming to a stop. On Subaru it is documented across 6 models: Forester, Outback, Ascent, Crosstrek, Legacy, Impreza.
What are the most common causes of P0740?
The most common causes of P0740 are: Faulty torque converter clutch (TCC) solenoid, Low or contaminated transmission fluid, Wiring or connector fault in the TCC circuit, Worn or failing torque converter, Valve body wear or sticking valves, Internal transmission electrical short, Faulty transmission control module. The specific cause varies by vehicle.
How much does it cost to fix P0740 on a Subaru?
Published repair estimates on Subaru range from $200 to $9,000 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0740 on a different make?
View P0740 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.