How to test for coolant in oil?

To test for coolant in oil, you can use a few methods. One common approach is to inspect the oil for a milky or frothy appearance, which can indicate the presence of coolant. Additionally, a simple test involves using a coolant tester or refractometer to measure the freezing point of the oil; diluted oil due to coolant will have a lower freezing point. For more accurate results, sending a sample to a lab for analysis can provide definitive information on coolant contamination.