I have heard to use ATF, and I have heard not to use ATF due to the qualities of ATF not being compatable with the seal material.
For piece of mind I use steering fluid instead of ATF (regular fluid from Pep Boy's, not MB fluid). Only costs a little more.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.