I have a 98 Subaru Legacy GT wagon.While driving up my drivewa yesterday I noticed the AWD wasn't working.The driveway is grave covered with a moderate incline but never presented a proble before.There seems to be no power to the rear wheels at all.Unti this happened the car seemed fine.There were no tell-tale signs of driveline problem.Does anyone have any idea to where I should star looking for a solution?I do the majority of my own maintenance an repairs but being a first time Subaru owner, I'm unfamiliar with thi vehicles AWD system.Any help would be would be greatl appreciated.Thanks