hey, post a pic of the new rims/tires. and a link to where you got them if you dont mind.

i packed my center diff with really thick grease. it still unloads to the front tires when they get off the ground, but not as much as they did before.

i hessistate to lock the rear diff. i think it would put alot of strain on the other parts. and i dont think a locked rear diff will help handling much. may even hurt it.