I changed my oil a week ago at a local oil changing business, Oil Can Henry's. My car is now leaking oil. Oil Can Henry's said that the oil filter is on securely and it is not leaking. However, the leak is coming from the oil cooler that sits right above the oil filter housing. They believe that it maybe a worn gasket. If this is the case, how much will this cost to fix and get repaired? My 2007 Mazda CX-7 has 85,000 miles. There was no leak prior to taking the car to get the oil change.