Hello Paul, I am based in Kenya and I bought the Toyota Harrier 1998 from Uganda. However, it does not shift to gear 4. Two months ago, I replaced the gearbox but the car will sometimes drive to gear 4 and fail other times. Is this a common problem with this car?

Hello, there are several other factors that lead to automatic gearbox malfunction besides a damaged gear solenoid or the valve body and gear clutches. That is why correct diagnosis is crucial before you go on a parts buying spree.

The automatic transmission control unit or computer can cause failure of number 4 gear solenoid response.

The wire harness from the transmission computer to the gearbox valve body can also cause specific gear failure and should be checked. Occasionally a bad throttle potentiometer will also affect the quality of gear shifts.