Hey all -
I just wanted to post the result of something that interested me. My dad's 1991 350SDL has had a problem with heating beyond the operating zone for quite some time, and without repairing anything else, the replacement of the exhaust system elimintaed the problem. My mechanic swore up and down that such a result is impossible, but he has to agree that it is no longer running hot. The car has 169,000 miles on it, and it was running the original exhaust system. We literally did nothing else this time around other than replace the exhaust system from the head pipe back.
Any idea why this should make the car run cooler because we have none?