I brought my car in for an oil change about a month ago and waited for the completion, estimated at 1 hour. They said they found evidence that my water pump had been leaking. The reserve reservoir was done about and inch, and they used a black light to show me some bits of spray. I didn't have time to get estimated $600-$800 repair done so left when oil change was done. When I got home, I refilled the reservoir to the recommended coolant level and have monitored it for the last month. It hasn't dropped a bit and there has been no more "spray". The car has been well maintained and only 70,000 miles or so. The whole thing has spoiled me on their shop. Good luck if you use them.