A bit late, but I had to dig around a bit for just the same query on another forum . As my machine is fitted with HIWIN Linear Rails and Ball Screws, I tracked down the following:-

Hiwin oil specs for standard use here:- http://www.intercom.si/web/dokumenti...om=80,-590,849

Mobilgear 630 (the easiest to find detailed information on) here:- http://www.ulei-mobil.ro/pdf/MobilIndustrieDataSheet/Mobilgear%20600%20Series%20pds.pdf

As I have access to large quantities of ISO 220 Slideway oil, I use that.

Nick.