Hi Peter, couldn't find much on that particular model but I believe the self propelled mechanism doesn't need servicing except for belt tension. The rear wheels are held on with metal single use clips that I push on with a socket. I guess you will see them when you pop the hubcap off.
I've never pulled the rear wheels off my Procut 560 because it rarely gets used but the John Deere I had used to come apart every 6 months for a clean and regrease with a light/minimal grease application to minimise dirt sticking.
Try this for a bit of an idea
http://www.rover.com.au/files/editor_upload/File/04016218-I_ProCut.pdf
