I am getting ready to change out my fork oil but the hold up is "What weight to use" and "What brand to use"? The MoCo has type "E" which is about a 10 wt. and SE at 15 wt. and SE Heavy at 20 wt. There is also Belray at 10 and 15 wt. Do you use just one weight or mix to make your own blend?
With the Progressive standard height springs, I used a mix of 10 and 15 weight, and was pretty happy with that. I have learned to change the fluid every year (about 20K). It's always nasty looking. I installed the Ricor Intiminators last year and like Dawg said, use the 5w they reccomend. I am no longer trying to improve my fork performance, it's that good. I don't know of any difference in brands, as long as it is a name brand, including HD.