Hello, I have an 06 Solstice with LSD and manual trans. I took a 1,000 trip in my solstice and on my way back home all of a sudden on the freeway doing 70 I hear this loud scraping noise and my car decelerated quickly so I pulled over and looked under my car because it sounded like my exhaust had fallen off or something. Everything looked normal so I went back and started driving again, now whenever I accelerate or decelerate I hear this awful grinding noise. The noise is loudest when going 20-50 mph. It sounds almost like someone filing a piece of metal and you only hear it when the vehicle is moving. I went and got diff fluid and additive and I'm going to change it but has anyone else experienced this and know what it is?