On my 95, the belt driven fan sits behind the radiator and the electric fan sits in front. The belt fan pulls the air across the radiator and into the engine compartment. The electric fan pushes the air across the radiator then into the engine compartment. The air moves the same direction, from the front of the engine across the radiator then into the engine compartment.

Was the fan clutch replaced? Certainly check the fan clutch. The symptoms could be caused by a bad clutch. At highway speed the vehicle moves enough air for engine cooling. At stop and go or city driving, the fan must move the air. A bad fan clutch will not turn the fan fast enough to move the necessary volume of air. Similar to an automobile clutch. If it slips, the vehicle won't go. If a fan clutch slips, it won't move air.

Let the vehicle warm up to operating temp. Open the hood. Shut off the engine. The fan should stop almost immediately. If it continues to turn, it needs replaced.

You can also check by getting the vehicle up to operating temp and shutting the engine off. Open the hood. Try to turn the fan by hand. It should be very stiff. If it turns easily, the clutch needs replaced.