2 nights ago I started the truck waiting on the wife in the driveway started to hear a whine like a belt or something tapped the gas and it stopped. When I backed out I noticed a puddle on the driveway of coolant. I looked yesterday for where it could be leaking put some in ran the truck around the neighborhood no leak or signs of a leak the check engine light was on so I ran over to Advanced to check the code nothing came up. I am at a loss any ideas. Couldn't happen at a worst time taking it 3 hours away this weekend

 

Generally a loss of coolant leaking on the ground would point to a water pump. Are you sure the water on the ground was antifreeze and not from the A/C. My 2004 GMC had a loss of fluid which stopped for a while then came back. It turned out to be cracks in the heads (both).