Got a “Rapid Response” call on Friday from the service manager at my local dealer to tell me I need to bring my 2004.5 Cummins in to have some test done to check the engine soft plugs. And to avoid driving the vehicle until the plugs are tested. I have noticed engine coolant leaking a couple of times and wondered if anyone has heard of such an issue?

 

I haven't heard of that but mine is going in this week to reseal the thermostat housing, it is leaking.

 

Yes. Some of the early 600's got out of the factory with freeze plugs that could leak.
Also, check to make sure the block heater it tight, that's another source for a coolant leak.

MikeyB