U340E Transmission Valve Body P377402 for Toyota Corolla

A complete replacement valve body, part P377402, for the Aisin U340E / U341E / U341F 4-speed automatic. That family sits behind the small Toyota engines: 2008-on Corolla 1.8L, 2006-on Yaris 1.5L and 1.6L, 2004-2007 Scion xA and xB 1.5L, and 2000-2005 Celica GT 1.8L.

The U340E valve body wears in the bores after high mileage, and the result is a harsh or late 2-3 shift, a flare between gears, delayed engagement into drive, or shift codes that come back after the solenoids have already been swapped. A worn valve body also loses line pressure, which burns clutches, so it is worth replacing at the first real symptoms.

To install, drain the fluid, drop the pan and filter, unplug the solenoid connectors, unhook the manual valve and detent spring and unbolt the valve body. Watch for check balls and accumulator springs as it comes down. Transfer or install solenoids as needed, torque the new unit down in the factory sequence, refill with Toyota WS fluid and clear adaptives before a road test.