Car Shakes/Jerks while Accelerating

I have a 2000 Intrigue with 102,000 on it. The Transmission was rebuilt about 4,000 miles ago and just had the plugs changed Friday. Under slow acceleration at 35 going to 50 mph the car shakes/Jerks. The RPM jump in 25 to 50 at a time and it is not smooth. It only happens in the final gear, when it down shift into the passing gear it is fine. What can be causing this?

Sounds like an issue with the torque convertor solenoid or the torque convertor itself. If the transmission was just rebuilt, then take it back to the garage were the work was done. This should be covered under the warranty.

They will scan the transmission to see what is wrong.