It depends on the supercharger set up. I have a v6 and if I can remember correctly all the ones I found had thier own oil for the supercharger except maybe the x charger. I have not looked at the v8 blowers but it is probably just a brand to brand thing.
2008 v6 Pony Package. Performance mods: Aluminum Driveshaft, Screamin' Deamon Ignition Coil, Red Livewires... and an STS turbo kit with an intercooler,and water methanol injection.
5 psi~ 286rwhp, 331 rwtq
Other Mods: Window Louvers, 2 10" MA subs, 1200 watt RMS Hifonics amp. Tial 50mm BOV.
The GT 500 has it's own "lifetime" internal oil supply. There is a check plug on the front of the S/C though, removed with an allen key, that can be removed to verify the oil level. I think this is reccommended every 30,000 miles by Ford if I recall correctly.