ok guys so i did a search and only found about one person who was having a similar issue to me but could not find a solution to it.
heres the story, i recently bought my evo 9 about a week ago and been driving it around and i gotta say its pretty damn great. my only real concern right now is that when im driving i hear a distinct squeal from around 1500 rpm to 2000 rpm coming from what seems to be the rear of the car. the squeal sounds like squealing belts on a old car or a bad idler pulley. i take the car for quite a few test drives and get it up to speed on the highway and throw it in neutral at like 50-60 miles an hour and the car is whisper quiet. no noises besides this one in any gear except for the one i just described. has any one else experienced a issue like this? i hate to think its the rear diff but when i think about it if it was the rear diff wouldn't it make noise all the time? the only thing i could find close to a solution is to change the fluid in the rear diff, check the carrier bearing for the driveshaft, and check for exhaust leaks or exhaust rubbing... its such an annoying and embarrassing sound. besides that the car is great. any advice is appreciated and thanks in advanced! also if it came down to the rear diff needing changing i can get one off a friend of mine only thing is its a MR diff. not sure if the MR and GSR rear diffs and Transfercases are interchangeable.