Toyota U151E / U250E

Toyota's transverse five-speed automatic — behind the V6 Camry, Avalon, Highlander, Sienna and Solara, and the Lexus ES and RX. The U250E is the four-cylinder version of the same design.

It is one of the more durable automatics on this site, which is worth saying because it changes what a symptom means: on a transmission with a poor reputation an odd change is a warning, and on this one it is far more often the fluid, the engine mounts or a sensor.

The complaint that recurs is a harsh or delayed 1–2 change when cold, and it responds to a fluid change and a relearn in most cases. Toyota's WS fluid is not interchangeable with the earlier Type IV, and using the wrong one produces exactly this symptom in a transmission that was fine.

A shudder felt as a light vibration at a steady 60–80 km/h is the torque converter lock-up clutch, not the transmission slipping — the same fault every lock-up automatic on this site shares, and the same first remedy.

The U151F is the all-wheel-drive version, mechanically the same gearbox with a transfer case attached; the extra letter is the only place the difference is written down.