A buddy of mine has 33s on his sammi. Stock axles with lock rites front and rear, hes pretty hard on it and it hasnt broke a birf or rear axle yet.
If you do some hard wheeling or your in genral pretty hard on the sammi you might want to get birf rings or even after market birfs, such as the double tuff ones.
Hes also got the 6.5:1 Transfercase gearing in it, that is the perfect gearing for 33s. Its scoots down the freeway alright to.
Hope that helps
Amilla