What do I name the mount of the wheel?

[Pi]

For most vehicles there are four "hub"s. You name those hub0 -hub3. But what do I name the joint on the actual wheel model?

Here is a bad pic of my problem:

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[Thalberg]

Did you try using the wheel without giving a set name to the joint? It might just assign it on whatever joint is in the model, regardless of name.

[Plornt]

you dont add any joint you just center it on the grid

[Pi]

So, I really need to know the answer. Is it a joint, with or without a set name, or is it no joint?