I'm the original owner, until last spring always used synthetic oil. Switched to Jiffy lube and they put in conventional high mileage oil. 5w30 as required. In august I noticed a few drops on the driveway. Oil drops. I drove the car to FL and spent 3 weeks there. Oil life was still at 40%..STILLL FULL ON DIP STICK
When I got home to Long Island we had a very bad cold snap - 20 degrees. There were no issues during the trip home. I drove straight through to L.I.. We left 10 am and got home 4 am the next day. I used middle grade gas as the car ran better.
The car was loaded as we brought a lot back from FL with us. The only stops were food, gas and restroom.

The next morning there was a puddle of oil in the driveway. The front of the motor was covered in oil. I checked on line and it appeared the oil pressure sender was leaking - a warm day so I changed it. Car looked like it stopped leaking - then the temp dropped and the oil spots reappeared.
The leak was now obvious it was the oil cooler. The cold temps and lack of time forced me to get a local know shop to do it. They are great mechanics and take pride in their work.

The shop got the GM "O" rings and did the work. It took 3+ hours of shop time. They bill was $375 for all the work. They gave me a discount because I am a regular at the shop. ( I take care of 8 cars)

People ask what it would cost, I can now say a shop will charge $400 labor and $100 in parts/ anti freeze ..etc. My shop cleaned the engine compartment and engine before returning the car.

 

 

Thanks for the information