Four-solenoid set for the Subaru TR580 Lineartronic CVT that controls torque converter lock-up and AWD transfer clutch pressure.
If your Crosstrek, Forester, Legacy or Outback shudders like it is rolling over rumble strips at 35 to 50 mph, binds up in tight parking-lot turns, or has set a converter clutch code, the solenoids on the TR580 Lineartronic valve body are one of the first places to look. This four-piece set covers the torque converter lock-up circuit and the AWD transfer clutch pressure circuit, and it comes with four new retaining clips so each solenoid seats the way it did from the factory. It is listed as a replacement for Subaru 31825AA050, 31825AA051 and 31825AA052, and it crosses to Dorman 926-408.
The TR580 is a chain-and-pulley CVT, so there are no shift solenoids in the conventional sense. What it does have is a torque converter that locks up almost all the time once the car is rolling, plus an electronically controlled transfer clutch at the back of the transmission that decides how much torque goes to the rear wheels. The transmission control module sets both of those with duty-cycled solenoids. The lock-up solenoid controls how firmly the converter clutch is applied, and the transfer solenoid controls the clamping pressure on the AWD clutch pack. Because lock-up is applied so much of the time on a Lineartronic, a solenoid that responds slowly lets the converter clutch slip instead of clamp, which heats the fluid and glazes the clutch lining. A sticky transfer solenoid shows up in the driveline instead: the rear axle either drags in turns or never picks up drive.
Start with the fluid. Dark, burnt-smelling CVTF or a level that has never been checked will cause the same shudder, and Subaru released TCM reprogramming for some of these complaints, so ask a dealer whether your VIN has a pending update. Then measure each solenoid cold at the connector. On this set the torque converter valve should read 3 to 3.8 ohms and the lock-up valve 12.4 to 13.2 ohms; an open, a short or a reading far outside those windows condemns the coil. A coil that reads correctly can still be the problem, because these valves usually fail from varnish and clutch debris in the spool, not from a burned winding. Our guide to testing solenoids without a factory scan tool covers resistance and activation checks, and the Subaru Lineartronic CVT service guide covers fluid level and condition on this exact unit.
Listed fitment is the 2013-2023 Crosstrek, 2014-2023 Forester, 2015-2023 Legacy and 2015-2023 Outback with the TR580 CVT, and the listing notes the same solenoid bodies are used in the TR690 behind the six-cylinder and turbocharged cars. Subaru made running changes to this valve body over the years, so pull one of your old solenoids, compare the body, nose color and connector against the photos, and match the part number before you install. If you are not sure which unit you have, send us your year and VIN and we will check it. You can see every Lineartronic part we carry on the CVT parts page.
The solenoids live on the valve body, so the job starts with the pan off and the fluid drained. Photograph the harness routing and mark which bore each solenoid came out of before anything is unbolted. Clean the bores and the oil strainer, fit the new clips and O-rings, and torque the valve body hardware evenly so it does not distort. Refill with genuine Subaru CVTF-II and set the level hot by the procedure for your model year. Substitute fluid is the most common reason a TR580 comes back with the same shudder. After the job, clear codes and let the TCM relearn before you judge the result. If the pressure circuits still misbehave with new solenoids, the problem is in the valve body itself, and a complete TR580 valve body assembly is the next step.
| Pieces | |
| Fits | |
| Vehicle fitment | |
| Replaces | |
| Torque converter valve resistance | |
| Lock-up valve resistance | |
| Material |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It fixes shudder that comes from a lock-up solenoid that no longer controls converter clutch apply. If the converter clutch lining is already glazed or the fluid is burnt, new solenoids alone may not cure it. Check the fluid and measure the old solenoids first.
On this set the torque converter valve reads 3 to 3.8 ohms and the lock-up valve reads 12.4 to 13.2 ohms. Measure cold at the connector. An open or short means the coil is bad, but a good reading does not rule out a sticking spool.
The listing states the same solenoid bodies are used in the TR690. Compare your old solenoids and part numbers against this set before installing, and send us your VIN if you want it checked.
Genuine Subaru CVTF-II. Generic CVT fluids are the most common reason the shudder comes back after a solenoid job.
Clear the codes and let the transmission relearn. If your car is a 2018 Legacy, Outback or Forester with a P0841 history, ask a dealer whether the TCM reprogram from Subaru bulletin 16-111-18R has been done.
