Hello; I have a 2004 silverado 1500. I purchased newradiator hoses and heater hoses to replace he old original hoses at the next antifreeze change. Upon looking at the heater hose setup I noted a connection for one of the heater hoses that I am not familiar with. It is on the firewall and one of the heater hoses is connected (to the heater?) by it. I suppose some sort of special tool is required or perhaps knowing the trick. Maybe a special tool and knowing a trick is required? The other hoses appear to have the simple steel spring clamps. If this information helps, the hose in question appears to be the one that has a Y connection with a larger hose that goes to the coolant reservoir. This will be my first time replacing all the hoses on the 04 silverado. Even thou it has less than 36,000 miles on it, I feel that ten years may be pushing the safe limit with regard to time. Any pointers on this procedure will be appreciated.