P0700 on Subaru: How to Diagnose & Fix

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.

Early Lineartronic CVT Outbacks (2010-2015) have documented internal CVT failures — most commonly valve-body faults, but also chain/pulley and pressure-control problems — that can cause harsh or delayed engagement, RPM flare, jerking, limp mode, or complete loss of drive. Subaru acknowledged the problem with a CVT Warranty Extension to 10 years / 100,000 miles covering the CVT and everything associated with it (valve bodies, internal parts, harnesses, and leaks) on 2010-2015 Legacy/Outback (and related models). A revised/upgraded valve body is installed at repair. This is separate from the low-speed torque-converter shudder complaint; here the transmission can set fault codes and go into failsafe. Out of warranty, a full CVT replacement is a multi-thousand-dollar 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.

A TCU programming error allows the Lineartronic CVT to engage before the drive chain is fully secured, causing chain slippage that fragments the chain guide. Owners report shudder, hesitation, irregular noises and MIL illumination; in worst cases chain breakage causes loss of motive power. This superseded the earlier WUV-07 recall and is the basis for the April 2024 class-action settlement covering 2019-2020 Ascents.

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.

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.

The clutch throw-out bearing (release bearing) commonly develops a chirping noise that goes away when the clutch pedal is pressed. This is a known issue on WRX models and while the noise is annoying, it doesn't always indicate imminent failure. However, it should be monitored.

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.

Manual transmission BRZs commonly develop throwout bearing (release bearing) noise, typically a chirping, squealing, or grinding sound when the clutch pedal is pressed or released. The noise is most apparent in cold weather and often appears between 20,000-60,000 miles. While the noise itself is mostly a nuisance, a failed throwout bearing can cause clutch disengagement problems. Subaru has not issued a recall, but the issue is well-documented across both BRZ and Toyota 86 communities. Replacement requires transmission removal.

The 2012+ Impreza's Lineartronic CVT (TR580 for 2.0L models) is prone to harsh engagement, delayed acceleration response, and premature failure. The smaller TR580 CVT handles the 2.0L engine but can develop valve body issues causing harsh shifts into Drive/Reverse and a pronounced thunk when engaging gear from Park. The CVT chain can stretch, and the transmission oil pump can fail. Subaru extended the CVT warranty to 10 years/100,000 miles on affected models.