[Stocker]

Fresh coolant (30% to 50% antifreeze) might help, but I wouldn't think that's your problem. If you believe it's the fan, instead of spending the bucks for an aftermarket unit, try a junkyard. Look for one from a large late-model car, van, or truck - it'll probably be a more heavy-duty unit. One more possibility, though likely a long shot... Some fan clutches can be taken apart, and the fluid inside replaced. Mine is like that - it failed once, many years ago, and I found it was like a sandwich, with a front and a rear half, bolted together. I got a small vial of fluid at a Toyota dealership, and voila! No problems since!