On my U3 Scandisk Cruzer 8GB drive there is a "Cruzer" program that was
installed when I first plugged it in. The installation created a desktop
"Cruzer" icon. Clicking on it shows a number of options. Under Settings, there
is an uninstall option.
When I wanted the full 8GB for data, I copied the Cruzer files to another
location for later use if needed, and then ran the uninstall and said "Do Not
save the data files" I ended up with a reformat with 8GB of storage.