The plot thickens. Yes, Cummins 12v, the coolant reservoir level is down. I added a 1/2 gallon of distilled water to it yesterday. The stains I noticed yesterday were directly under the front of the block, this morning the 'puddle' is directly under the water pump; guess it's enough of a leak while running it's slinging coolant all over the place. Contacted the local Ram stealership, predicatbly not a cheap repair, but I'm not feeling good about getting on the Interstate to drive it to my mechanic in Orlando, and not interested in paying to give the truck a 'ride' there. If the dumb thing let go at 70 and puked all the coolant out I'd be very sad...........