My Hummer H2 was losing coolant. it wasn't a small leak, either. Water poured from the driver's side of the engine profusely. It wasn't a hose, the radiator, heater hoses or the heater core. I figured it out and fixed it in an afternoon. Come along with me as I diagnose and repair a problem that could happen to your vehicle at any time. This repair is the same for Chevrolet and GMC trucks. Let's do this!