Nos,
The two most common reasons I've come across for shuddering servos are 1. damaged/altered antenna on the RX. 2. a short on the PCB. this could be from a loose component on the PCB or a bad case of PCB frost.
where was the car stored? Was it exposed to really high humidity or prolonged sub 32f temps year after year? any detail you can give about the storage of the car would help