I had a Detriot No Spin installed in my rear axle about 6 monthes ago and I wanted to get a prognosis on a sound. When I let off the gas I hear a kind of grinding sound and then when I lay on the gas again it will make the noise again. At the points where the noise occurs it is like something in the drivetrain must be engaging and disengaging. I'm trying to determine if this is a Detroit thing, or if I need to investigate other sources for the noise. I don't really remember hearing the noise before the Detroit.