Wonderirng about this...I killed the 2 giants/mammoth combo outside whiterun a long time ago, they have yet to respawn, but their treasure chest does. Wondering if they will sometime as well?

Are you refering to Tumblearch Pass? If so I find that for some reason that single giant camp never respawns enemies for some reason...

Just in General. The camp I'm referring too is outside whiterun..two giants and at least one mammoth, and a chest as well, seems the chest respawns but the enemies don't. I love killing those guys. lol