I gave him my Nakhriin mask when he was my follower, he gone away when another follower take his place.......
Now i really dont know where is him!!
I waited in Whiterun for nothing...
I dont want to lose a dragon priest mask....

Best thing with the Circle members is that they have their own little GPS. Go to your journal, mark "Ask the Companions leaders for work" in misc quest section as active, and hopefully, this will lead to three arrows (one for Vilkas, one for Aela and one for Farkas) on your map.

If not - how long did you wait in Whiterun? Did you stay clear of Jorrvaskr? Leave Whiterun for 30 days if you still can't find him.

Thanks for ur reply
Well, Ive tried with the GPS, there are three arrows but one is for Skjor and not Farkas..
Im stayng in whiterun since 4 days ago(in the game of course), nothing, i cant find him....in jorvaskr too....
But i dont think hes died, he told me that hes going to home or something like this.
Edit: Why 30 days?

Skjor? You get Farkas as a follower after you complete the main questline.
Skjor goes on a vacation during the main questline. Don't know what you're talking about.
Does the marker lead you to Gallows Rock or some other place?

EDIT: Just realized that this was moved to the Spoilers section, sooooooooooooooo

Skjor dies in the quest line, how does the marker lead to him?

There's a bug that can cause Skjor to come back from his vacation and bug the radiant quests after his return which basically resets the quest marker to include him.

I cant use skjor as a follower and he keeps treat me as a recruit.
Hes still able to give me jobs.