Began making loud squealing noise

Question

My Kirby Generation 3 began making a loud squealing noise from the area over the rear wheels. I bought this one new, and it has always been used properly with no 'abuse'. Is there a port or opening that I am not aware of where I can oil the workings?? How can I check for bearing damage?? I am in a small town with no serviceperson, and am not sure where to start.

Help! Company coming Sunday, and need to waltz with Kirby before they arrive!!