i'm asking for my cousin... does anybody know where i could find aftermarket rocker arms for a 3.9? im not sure if they even make such a thing for that engine..just wondering. any companies that might have that?

Check out:

http://www.socaldakota.com
http://www.krcperformance.com
http://www.truckperformance.com
http://dakota.racenet.net

Lots of places :)