My 2005 Forester 2.5 with some 68k Kms recently started exhibiting a shudder when turning hard left or right at very slow speed such as when entering a driveway or exitting a parking spot. No vibration is evident during normal driving situations. Steering fluids, belt and steering rods were checked without result. A Subaru technician suggested changing fluid in both front and rear differentials which made no difference. Are there any suggestions as to where I should look next?