Rarka,
It appears that you are combining two modeling methods, a detailed model with tie rods (Rigid Elements) and then also spring rate manipulation. You should select one method and stick with it.

The detail model as discussed in the CAESAR II manual should have rigid elements spanning the length of the joint to dummy nodes. You then connect the dummy nodes via C-Nodes restraining the Y, Rx & Rz axis.

A spring rate manipulation model would use a zero length expansion joint, no tie rods (rigids). You should also set the OAL of the joint to ambient temperature.