300 seem to run fine on the freeway(temp gauge in the middle). Over heats in town(temp gauge at 3/4). In looking at the fan pulley on the 300C(overheating one) it seems to be about an inch larger in diameter than the fan pulley on my 300D(never overheats). Could the problem be this simple. Oh, the 300C(overheater) has a pulley with OD of 7 3/4 inches. The 300D(never overheats) has a fan pulley OD of 6 1/2 inches. Does anyone know what this measurement is supposed to be? Zak [Non-text portions of this message have been removed]