joser the poser

hey guys my moser 9inch and all the sudden its making the noise my 410 gears made when i had a 12 bolt, the weird thing is like at 90mph and after its dead quite, no whine, could it be the gears werent set properly, or what im thinking is that my punk as friend who picked up my car steped on it and the gears werent broken properly he swears 2 me he did not but i dont know, anyways i guess i will just keep it at 90mph all time