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Antifreeze in oil crankcase


I was doing an oil change on a 1997 sable, added one quart of synthetic oil, and then accidentally added about 4 ounces of antifreeze (picked up the wrong bottle). I drained the one quart of oil (and hopefully some or all of the antifreeze). Then I added 5 quarts of synthetic oil. I replaced the oil filter, but did not replace it again after the antifreeze incident. Is there anything else I should do?

Drive you car long enough to get to full engine temperature and stay there for a while. That should help boil off any coolant that may remain in the oil.

4 ounces of coolant isn’t much.

Then again it doesn’t take much coolant in engine oil to cause bearing problems as coolant makes a poor lubricant.

It MAY burn off and it MAY NOT.

If you have NOT started the engine since dumping coolant in, drain the oil/coolant and replace the oil filter again if only for peace of mind.

The techs on here may argue the point, but I’m not a tech.

I wouldn’t want to say go ahead and drive it, and then down the road you come back here and cut me up.

the immediate drain and refill and dilution of any minute amounts of antifreeze that may have remained, practically assures you of no problem. Do the math on dilution and you will see hardly any possibility of retention of antifreeze. The only question I have is the relative position of the filter and any ability for it to catch any…