I have a 2009 Laramie 5.7 L. The other day I saw liquid under the truck, not much but what was it. Was not sure. Checked engine oil, all ok, brake fluid ok, Power steering, down a tiny bit. Started up, all ok, a few miles down the hwy the high temp light comes on! Pull right over and stop. Called a buddy. Let it cool down. Turns out we topped up the rad and reservoir with a gallon and half maybe of water. Drove home, 20 minutes, truck ran perfectly, no leaks, not a drip. What? Put pressure tester on the rad cap next day, pumped it up to 14 psi and within 5 minutes I see wetness on the water pump at the T-stat housing where the upper rad hose joins. I squeeze the hose, aha! coolant squirts out. Changed the clamp (cut off OEM spring clamp with a dremel) undid a screw type hose clamp (2"), wrapped it around and tightened, problem solved. Old clamp must have been loosening when hot, leaking a bit at a time until finally coolant level was too low, and no, the low coolant warning did not work. Plan on replacing hoses and the rest of the clamps soon. Look for signs of dry streaks on your rad hoses indicating an intermittent leak and of course watch the coolant level. In mine you cannot see it. The reservoir has a dipstick! New one to me!
