Re: 2001 jeep grand cherokee 4.7 Hydraulic Fan Issues
The hydraulic cooling fan should run at around 500 rpm as soon as the engine is running, and will ramp up the speed when the engine coolant temperature rises above a certain level or when AC demands. There is a special fluid for the power steering system, but i´m running an other brand than the recommended one without problems. It should be a synthetic power steering fluid. It can be that the fluid you have used, is not the right one. The temperature sensor at least is not an input needed for the fan to run its idle 500 rpm, its just the way the circuit of the hydraulic motor is designed. Did you already feel by hand if the fan motor is not hard to turn?