reading all these posts about anti-freeze, a blind man can see u guys are misinformed. Listen to me, "Use the pre-mix anti-freeze thats approved for Cummings Diesel Engines" thats the best you can buy, it has nutralizing sloutions, with NO crushed glass, and a cleaning, and lube agent thats safe for all seals and gaskets. oh, wait?? you didnt know that anti freeze has crushed glass in it? yes it does Clem, duh !