I have a 98 chevy express van and it had been a very small leak would lose the entire overflow take after two or three weeks and the heat was a little weak but the van never over heated. I did some checking while the van was running and found it was a small drip of coolent from the water pump I put this in the overflow tank and went and started her up to my surprise almost immediately the dripping from the water pump stopped completely and the heat was normal again back to 142 degrees before it

It works. Not perfect although, two tries may do more justice, but I am concerned about clogging up the system. That's my review.

Had to pour it in my reserve tank because my radiator was full. Stopped the leak for about a week then the leak came back. After driving through the mountains in the desert it seems to keep my motor cooler than normal but not drastically cool enough to say for sure. I’d just go to a shop to get everything fixed.