Here's a thread about types of grease:
http://www.iceinspace.com.au/forum/s...highlight=lube
I used kero to degrease my skyview pro/eq5, and super lube synthetic grease to re-grease it. This mount was very stiff in RA prior to re-greasing but now moves silky-smooth. The only problem I had was difficulty getting the ring gear back onto the shaft - it needs to be kept dead-square as it is tapped back on.
Here's a series of photo's of a GPDX re-grease:
http://arnholm.org/astro/gpdx/index.htm
As long as your careful and remember where everything goes it's not a hard job. After completing the job it's nice having a greater appreciation of how the mount works.