DOES HEAD GASKET SEALENT WORK ON A CAD NORTHSTAR V8?

The head gasket issue in a Northstar stems from a single or multiple headbolt(s) pulling from the block. Sealer will make things worse, it can damage the water pump and clog the heater core. The person that said gm says to pour in a bottle when doing a coolant change is a lunatic. Up until around 2002 it was recommended to put in several sealant tabs in the lower radiator hose, that was just a recommendation that has since been lifted. The only way to fix the issue is to have all the head bolts removed and studded. For more info visit cadillacowners.com. there is a ton of information on your very question.