I have a 2009 mustang gt with a 5 speed manual, I have Recently replaced the limited slip differential and now I am experiencing a grinding/rubbing noise over about 45 mph . It sounds like the pinion rubbing against the case of the rear end , Would this problem be the cause of a pinion nut being too tight? If anyone could help give an Idea on what the problem may be I would appreciate it . If helpful I had a whining noise then went and tightened the pinion down with an impact its the only way I could get a turn on the nut im working in a driveway under the car can’t get a breaker bar underneath with me , after. Tighten it the whining went away but now there is a rubbing sound . Did I over tighten the nut?