I've never put it into my diff so should I put it into the diff in spite there is a grease? Which is the best for the central diff?

It all depends on what your doing. If your just bashing and want good acceleration I would go with a 10000/10000/10000(front,center,rear). You could also lock the center with a 100,000 weight and keep the front and rear at 10000.
If your racing, try 3k/5k/1k as a starting point or 5k/7k/3k.


Thats My .02 cents :-)

I have 7000 in the front 5000in back. Had to switch to 30000 in the center because too much power was going to the front. I started with 10000 in the center. Too thick in front you will push too much, too thick in back will make you squirrely. I'm running the ofna 9.5 ravager with 28.