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Pops_R's avatar
Pops_R
Explorer
Jan 04, 2017

Using Automotive Antifreeze in Black Grey Water Drains

Is there any harm in using the Automotive antifreeze in the gray water drains? I understand it is toxic and why why we use RV Antifreeze to winterize, but do not know if there is any concerns to da...
ktmrfs's avatar
ktmrfs
Explorer III
Jan 05, 2017
straight auto antifreeze isn't going to do you much good. Freezing point is about 8F. Freezing point drops when mixed with water. Lowest freezing point is around 50/50.

And like others said, don't use it. RV antifreeze is non toxic, and less expensive.

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