I purchased a 1996 XLT 5.0 V8 AWD. The vehicle has 81K but runs excellent. I have a humming (motorized sound) that sounds like a power steering pump (if you turn wheel too far to one side) that to me sounds loud. This sound is present at idle, park and appears to not change during driving.It appears to be located drivers side wheell well and under carriage area. When I questioned mechanic, he said this is normal with AWD. Any body have any suggestions, or comments. Truck under warranty and would like to fix asap if this could be a problem. email me swyllie@MSCLiquidFiltration.com