U660E Transmission Master Rebuild Kit with Frictions and Steels

This is a master rebuild kit for the Aisin-built U660E (FWD) and U660F (AWD) six-speed automatic, the transaxle behind the 3.5L 2GR-FE V6 in the Toyota Highlander, Avalon, Camry V6, Sienna, RAV4 V6 and Lexus ES350/RX350 from the 2006 model year on. It covers the soft parts you replace on a full teardown: friction and steel clutch plates, the overhaul gasket and seal set, and the sealing rings.

The U660E usually comes in with harsh or delayed 2-3 and 3-4 shifts, flare on the upshift, or a slip code once the clutch packs are worn and the linear solenoids start compensating. Once the unit is out and the packs are cooked, a kit like this plus a fresh filter and properly cleaned valve body is the standard fix.

On the bench: tear down and clean the case and drums, soak new frictions in Toyota WS fluid before assembly, replace every seal and sealing ring in the kit, then check clutch clearances pack by pack against the factory spec as you stack them. Refill with Toyota WS only and run the fluid level check at operating temperature through the overflow plug.

Confirm your transmission is a U660E or U660F before ordering. The 4-cylinder Camry and RAV4 use the U760E, which is a different kit.