The lubepoint you are looking for is only on the newer trucks, I'm thinking it started in the 04.5-05 model year.

 

My 03 does not have one. As a matter of fact the one side is split.

 

Spoke to a guy in a Dodge service dept today, has a 4x4 and knows the ball joints. Says 1/8 up and down is OK, any other play is bad. Also got the hypo needle for the greese gun and added to the ball joints and steering joints. Can't hurt.