Issue with Hinge Joints as of Unity 5

Hi,

So I had a project I created several months ago when Unity 4 was the latest version. I installed unity 5 and brought in some parts of this old project and I'm having issues with hinge joints that I really can't figure out.

My project is a simple robotics simulation. When I loaded the original version, my simulated robot appeared in several pieces thrown about huge distances apart from each other.

Once I figured out the issue was with the hinge joints, I commented out most of the code and simply added a cube primitive and a cylinder primitive, gave them rigidbodies, gave the cylinder a hinge joint with the cube as the connected body. And those have the same issue.

I made sure that enable collision is off. That the local anchor positions are appropriately set.

I'm really scratching my head over this. I hope I'm not missing something silly

As soon as I let the program run for just a single timestep, the two game objects pop apart. With just the one joint, they pop apart and rotate around some other point, but with more, things get a pretty messed up quick.

I tried checking documentation or changes, but everything seems to be set correctly. I'm not sure what I'm missing :/

Attached screenshots showing the joint initially, as well as after one timestep.

 

For reference, this is what the joints were being used for in unity 4.

http://imgur.com/a/vbhD7