In a Nissan RE4FO4A or Villager 4F20E, slipping or no second gear may be caused by insufficient spring tension on the 1-2 accumulator piston or a stuck 1-2 accumulator regulator valve.
We have in-depth information on retrieval of diagnostic trouble codes for Nissan vehicles.
Harsh upshifts on electronically controlled Nissan transmissions may be caused by a faulty dropping resistor or a poor connection at the resistor.
In Toyota Previas with four-cylinder engines and A46DE transmissions, stacked shifts or no passing gear may be caused by a broken wiring harness or faulty throttle-position sensor.
GM introduced a new-design overrun roller clutch into the THM 4L80-E as a running change beginning in March 2001. We cover the parts affected by this engineering change.