You Have a Stuck Solenoid Automatic transmissions shift gears due to the action of the solenoids. ... However, sometimes these solenoids can get stuck and can prevent your car from shifting gears entirely. The most common cause of a stuck solenoid is the failure to replace your transmission fluid when you should.
Why does my truck stay on first gear?
Low or Dirty Transmission Fluid – Low or dirty transmission fluid can cause a car stuck in first gear automatic transmission. Your transmission fluid should have a light red/pinkish color. Dirty automatic transmission fluid has deep red or dark brown color.
What causes a truck not to shift gears?
If when you put your vehicle into gear and it won't move, this may be a problem with low transmission fluid due to a leak, the shifter, shifter cable, or it could even be a problem in the valve body of your automatic transmission.