Your transmission bands are bad, you need to replace them to make it work properly again.
If this is an automatic transmission, which I am assuming it is it will not work the same as a standard. Only drive it in overdrive or 1st gear.
Check for a blown fuse.
your transmission could be shot. if it will not shift at all, then you will need a new one.
A 2000 Jeep automatic that is not shifting correctly after it gets hot might have something wrong with the speed sensor that is located in the transmission. The speed sensor tells the transmission what gear to shift into at certain speeds.
Check the fluid. If full, take it to the trans shop.
Could be a pump problem or broken planetary. Regardless, the transmission will need to be disassembled.
reverse drum inside of trans is stripped out the fix is teardown unit and replace with abeast drum from transtar
You have to know whats wrong with the transmission before you can fix it.
if it is not going into gear when it is started, if it is a standard transmission then it could be that your clutch is not engaging or that your gears are stripped in the caseing of the transmission, if it is an automatic then your torque converter could be bad or there is something wrong with the shift linkage
The transmission will shift to the appropriate gear, if it's functioning properly. Otherwise, you'll either run really high RPMs, or you'll bog down.
Type your answer here... My Allison transmission will only down shift, whats wrong with it?