OK, maybe this is not exclusive to synthetic oil, but my primary colling fan motor burned out a couple of weeks ago. I thought maybe the A/C was not blowing as cold as it should when I was stuck at lights. When the temperature reached 100 outside I thought I had a cooling issue because the temp gauge would go up a bit if I had to sit at a light for more than a couple of minutes, but it would drop right back down as soon as I started moving.
I have a new fan on order and I removed the old one thinking at least the radiator would get a little better airflow for the next few days. I know that a friend of mine used synthetic oil a number of years ago to keep a car with a missing fan shroud from running hot in the summer. I am just amazed the car is not overheating with the big fan not working.
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