JD 850 Rear wheels locked up?

Hey guys and gals. I am stumped. I picked up a JD850, will be doing a rebuild on it but after sitting 2 weeks, both rear wheels are locked up tight. No release with clutch, diff lock, anything. Relesed the brake linkage, no help. I tight something had ceased so we tugged it to release possible ceased breaks but it is locked solid. Any suggestions are appreciated- I am at the point where I will have to take the wheels off and investigate but I don't really have the time to tear down everything. We need to get it moved to our new place. Wheel dollies don't really work up the ramps on a trailer. Thanks in advance. We have most tools here for repair, just looking for possible culprits to save time.