I have what looks like it might be a water pump bypass on my gmc. Didn't notice/think much about it til today when I pulled it out of storage and was checkin it over. It connects from the lower part of the thermostat housing to the water pump. My truck likes to run warm (190) on the interstate and I am wondering if this bypass is really necessary since water is going around in circles instead of through the radiator. Before I blindly rip it off I have to ask: Why did gm put it there in the first place?
jason
