One problem related to radiator has been reported for the 2006 Dodge Ram 3500. The most recently reported issues are listed below.
The water pump split at the seam in the case. When the engine was running, the pump would spray out a powerful stream of hot radiator water. The radiator water would be completely drained from the system within 30 minutes if running the engine, but the water would only escape slowly if the engine was not running.