CVT Transmission Fluid Type SB2 for Subaru TR580, 5 Quarts

Idemitsu is the fluid Subaru builds its Lineartronic CVTs with, and Type SB2 is that same fluid sold under the Idemitsu label. It is blended to the Subaru CVTF-II specification, the fluid called out for the TR580 chain-drive CVT used across the 2010-and-newer Forester, Outback, Legacy, Impreza and XV Crosstrek. One 5-quart bottle, Idemitsu part 30041113-95300C020.

CVTF-II is not interchangeable with the older CVTF (green) fluid, with the high-torque CVTF-HT used in some turbo TR690 units, or with any conventional ATF. The chain and pulley faces in a Lineartronic depend on the exact friction coefficient of the fluid to clamp without slipping, so pouring in a generic multi-vehicle CVT fluid is how these units end up with shudder at light throttle and eventual chain damage. Check the fill spec stamped on your transmission label or in the service manual before you pour, and do not mix specifications in one unit.

A Subaru CVT drain-and-fill takes roughly 5 quarts through the drain plug, which is why the 5-quart bottle exists. Drain warm, replace the drain plug crush washer, refill through the fill plug or charge pipe, then bring the fluid to the temperature window called out in the service procedure and level it at the check plug with the engine running. There is no dipstick on most of these, so the temperature-referenced level check is the only way to get the fill right. A full fluid exchange takes two or three drain-and-fills, since a single drop only pulls out about a third of the charge.

If the car has a shudder at 20 to 40 mph or a hesitation off idle and the fluid comes out dark or smells scorched, fresh CVTF-II is the first thing to try before condemning the valve body or the torque converter lock-up solenoids.