This thread must get the prize for the most speculation with the least facts. Maybe we should broaden the aproach... you don't suppose it's the whitewall tires causing it? Or detergent oil? Maybe he drove 60 mph all day and that did it? Let's all HOPE it's not the dreaded hydraulic brakes!! I had this exact problem one time, it was a slipping radiator belt, except that was on a 1980 datsun...it had low blinker fluid as well.
it's been fun watching this one.