Owners' Reviews

2003 Yukon SLT. About 3 months ago my "low coolant warning" signal came on. So I took the truck in, they topped it over and said to just monitor it till I brang the truck back in a few weeks to do my routine oil change. A month later, sensor went off again. So I took it in to do a pressure test. They said the test came back okay, but that most of the liquid in my reservoir was water. So I had them do a complete flush and refill. Its been about two months since I've done that and my sensor has gone off again. I checked the reservoir in the morning, coolant was up to line on reservoir. Checked for any leaks from hoses, etc. no visual leaks from hoses, etc. No visual drips on ground. I went to check it again in the afternoon and the coolant went down about 1/2 inch. I don't know if just opening the reservoir will do that? But, I can't figure out what's wrong. It can't be a bad sensor because when I top it off, the sensor doesn't come back on! Any suggestions on what could be wrong?