I have a 2005 Tahoe with the 5.3 engine and would like to drain and refill the cooling system. The shop manual says it is necessary to disconnect an air bleed line between cylinder banks to allow air out of the block. That proceedure looks like asking for trouble. I'm just wondering if I could achieve the same thing by disconnecting the top radiator hose. The thermostat is not connected to the top hose so I think it should allow any air to bleed out as I refill from the coolant bottle. Comments ?