How to make boogies follow a track

Hello, I have a train car with 2 boogies. I would like to make them follow right the track. Now I’ve used the iTween script in order to create the path and with the script rigidbody I’ve joined the two boogies but when I start the test, the first boogie follow the track but the second one makes the same movement of the first one. I would like that second boogie will make a curve when it begins and not when the first one begins it. Do you have some ideas? Thanks!

I dont know how to use itween but

If your trains are short and you dont mind using physics here’s my setup for mining carts which I tried earlier with each being a boogie of a larger box attached by joints:

Each wheel is approximated with sphere with a rigidbody and a joint to let it rotate. Then, to guide the train: between the rails are 2 frictionless spheres that have physics disabled for everything except the rails. Another script makes the center of mass low between the rails. video of it: Some games in Progress in unity - YouTube