not enough fluid, check the fluid level while the car is hot and in nuetral. Another thing to watch for suprisingly enough, is the speed sensor. Mine does'nt shift when warm, and also the speedometer needle won't move when it starts to act up. Was told if the speed sensor is'nt working it won't let the computer know you're moving, so it thinks your stopped so stays in first gear, even though you're driving. I thought it was a tranny problem, butnow know it was'nt. Something for you to think about or ask about before purchasing a new transmition.
Bad seal? Bad cooling line to radiator?
Bad pump Bad torque converter
Broken transmission mount? Bad "U" joint? Bad center bearing? Driveshaft out of balance?
A bad transmission.
Low or bad transmission oil, bad transmission solenoid, vacuum line issues, worn transmission gears, bad torque converter.. all possible reasons.
bad seal, the transmission is under your car by the road itself, if the seals are bad, water dirt and other debry and can penetrate (bad)
Check fluid level, is the vehicle warm or cold when this happens. The torque convertor may be bad. The transmission may need to be serviced (new fluid,filter, etc).
Bad seal? Leaking cooler line?
Poor driver or bad transmission.
Possible causes include a bad tire, a failed wheel bearing, a failed transmission bearing, etc.Possible causes include a bad tire, a failed wheel bearing, a failed transmission bearing, etc.