A couple of weeks ago coming home from the shore my transmission started to wine - sounded like a bearing or water pump. Anyway I've isolated the noise to occurring only in 5th gear - noisyest between 50-60 especially when you are on & off the gas. At 70-80 it seems a bit quieter. I changed the transaxle oil - 75W90 synthetic (55k on the 2009 WRX wagon) and did notice some very fine shiney particles in the old oil; but little or none on the magnetic drain plug. Any ideas ?