Originally Posted By: TheMAN
how many miles is on that ford? if it has a lot of miles, you should check the fan clutch... a marginal fan clutch will give you symptoms like these despite the fact that the engine doesn't overheat (yet)
Fan clutch has material inside that is similar to a brake shoe. And like a brake shoe it wears out. When it does, it slips much more than it should.
Check to see if a heavy duty clutch is available for that vehicle. Many vehicles that have clutch fan have a heavy duty version available. Some vehicles have a verity of fans, such as 5 blade 6 blade, 7 blade. Sometimes you can improve the air flow by upgrading the fan blades and at the same time go with a heavy duty clutch fan.
