My car has 70000 miles.
My car has an automatic transmission.
It sounds like the transmission is in fail safe mode. The shifting in your truck is controlled by the computer, (PCM). There are 2 shifting solenoids, a 3-2 downshift solenoid, a line pressure solenoid, and a TCC (torque converter clutch) solenoid. The PCM also uses sensor input from engine sensors like the throttle position sensor, engine speed sensor, and several more.
If there is a problem in any of these circuits, the transmission does not have the information it needs to shift properly, and will default to third gear, while second and first can be manually shifted.
The Check Engine Light should be on and stored any trouble codes. If the light is not on, the computer may not have detected a problem, but one of the shift solenoids is not functioning. The first step would be to check for codes and check the fluid level. If the transmission does not slip in any gear you select, the problem is most likely electrical, but it could be an internal issue as well. If you would like to have your shifting issue diagnosed, consider YourMechanic, as we come to your home or office to inspect and repair your car.
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