Originally Posted by Arakor
I...What would the valve cover gaskets have to do with it?
I suspect that the question about the valve cover gaskets was meant to help determine if the oil on the base of the supercharger could be from a leaking valve cover gasket, but it could also be due to a leaking LIM gasket.
Where exactly is the oil on the supercharger? If the supercharger'* nose seal leaks oil, it'll run down the underside of the nose down to the base of the supercharger, and that doesn't sound like what you've described..but the Teflon supercharger oil seals do tend to leak a little.
This is just my opinion, but if your supercharger has 128,000 miles on it, I'd recommend replacing not only the coupler, but also the oil seal and the nose bearings while you have it apart.