82 300SD Overheating Problem - Pulley?
My 82 300SD with 202,000 miles has been running hotter than it should be at highway speeds above 70 MPH. Not at red line but uncomfortably above the 100 degree mark and at 110 degrees ambient was getting close to red line last summer. At slower speeds and idling it does not run above 100.
My mechanic thinks he recalls there was a mfg modification to the water pump pulley in later year models like after 84/85 that replaced the pulley with a smaller one to make it turn faster.