1999 ram jerks when turning like it's in 4x4 but the front drive is not turning so I know it's not in 4x4. Where should I start looking? U joints? 

Can you confirm its front end? My limited slip is messed up after a rebuild and it grabs when cornering. 

Could be! Put new gear oil in it a while back and done the figure 8s. It started becoming harder to take out of 4x4 and then this happened so I just assumed it was the in the front. Yes I know what happens when I assume something. Lol 

Did you put the LS additive in when you changed the fluid?

 

L8tr

D