Alloy wheels (oem)

I have the factory aluminum wheels on my 2002 wagon. Recently I was replacing the front brake pads, and I thought it would be a good time to rotate the tires. Fronts came off no problem - just a light tap - but the rear rims are "frozen" onto the rear brake drums. If I ever had a flat on a rear wheel, I would be SOL!

I didn't get under and pound on the wheel as the car was not securely supported, but I noticed that there four small indentations in the inner face of the wheel where it mates up against the brake drum. I tried squirting some penetrating oil in there, and pried with a big screwdriver, but got no result.

Is there a trick, or just brute force? I hate fixing machinery with a hammer!!

Yes, they just come off, no trick to it but they do fit tightly.