It’s fan clutch season.
Warmer temperatures are drawing more attention to the little part that keeps truck engines running efficiently. Fan clutches engage when coolant and the radiator can’t keep an engine’s temperature cool enough to run at its best, turning on a fan to cool the engine quickly.
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“Fan clutches allow the engine fan to engage and disengage based on the truck’s cooling demand,” says Michelle Collins with BorgWarner. “To run the engine fan at full power requires up to 90 horsepower. Having the fan run at full power only when needed helps save fuel.”
When spring starts to heat up, that’s when many drivers notice their fan clutches aren’t working well or at all, and that’s when trucks end up down, says Kate Diecks, sales manager with Kit Masters.
“There’s only so many engagements before that friction material wears down or those bearings go bad,” then trucks sit overheated on the side of the highway, she says. “A lot of fleets will change the fan clutches at 400,000 miles or four years, because if your fan clutch goes bad, you’re stuck on the side of the road, and it’s a huge bill.”
BorgWarner makes on-off fan clutches and air-sensing viscous fan clutches. There are two configurations of on-off fan clutches, Collins says, the K32 and the DuroSpeed. Air-sensing viscous fan clutches come in three variations, the 750, 795 and 805. Each fan clutch is best suited to a different working environment.
