When I start to slow down, the vehicle starts jumping like its hung in high gear and I have to press the o/d off button on my gear shift to stop it. Also,while driving down the road, when I let up on the accelerator the transmission starts jumping.
One of the solenoids or valves in the transmission’s valve body is hanging up . Look at the fluid color ( wipe stick off on white paper) if it is brown instead of bright pink, you can try a filter and fluid service ( make sure to use Mercon V this is full synthetic fluid required in this vehicle) . If the fluid is pretty pink you can try putting an additive called ” Shudder Fix ” ( can be found at auto parts store ) this may be a good thing to try before tearing apart the transmission. You may want to check the VSS (to make sure it is sending the proper signals ) also before tearing it apart.Feel free to check out some of the other resources on the website as there may be some helpful information available.