The route I did was a loop starting from Momyer up the road to vivian Ck, then up the normal trail to Gorgonio - I've just found the description I used which is pretty much precisely the route I took:
https://www.summitpost.org/san-gorgonio-9-peaks-challenge/793559

There was no snow at all in October. You're right, in snow it would be tough (tho' at least your pack wouldn't need so much water!). Personally, it was close to my limit for a comfortable day hike. _Much_ harder than e.g. cactus to clouds for San Jacinto.

I assumed it would be dry the whole way and took 6.5L of water (drank it all!), although I could have filled up a few miles in at the camping area on the way up Gorgonio.