QUESTION: I have an ’00 Ford F-250 I use to haul a small backhoe to job sites. The trailered load is about 10,500 pounds. The truck never misses a beat and runs great, but the 4R100 automatic transmission’s and 7.3L engine’s temperatures creep way up in stop-and-go traffic and on long grades. I am thinking the fan clutch may be bad, causing both issues described. I have an electric fan running continuously on the outside of the transmission cooler. Your thoughts?
ANSWER: One of the common upgrades ’99-to-’03 Ford Super Duty owners make is replacing the stock transmission cooler with one from an ’03-to-’07, which has a very robust cooling design. It’s a simple swap that usually results in temperature drops of 20 to 25 degrees across the board. The original transmission cooler on the ’99-to-’03 7.3L trucks is a puny nine-row piece compared to the 31row version used on the later-model rigs. You should also check a few other items: The torque converter could be going out, causing excessive heat buildup, and/or the fan clutch and water pump need to be replaced. But first, whenever there’s an overheating issue with those older engines, it’s a good idea to thoroughly flush the cooling system and replace the thermostat, then check off the other components that are integral to the cooling system as a whole, if a problem is still there.