i had the problem and its the hose as do many others with the 4.7, leaks at the tread on the pump. its a common problem
jeep made a newer version hose to fix the problem http://www.justforjeeps.com/01grch4hypos.html
no one else sells it so order it other then jeep so order online or at your local dealer.
also the 4.7 uses special PS fluid since its a Hydraulic system, called MS5931 only sold at the dealer and runs about $10 a quart. if they try to sell you ATF+4 dont take it