Research between different campuses of the same university
With the growing prevalence of networking technology, collaboration is easier than it ever has been before. I would think that collaboration across two campuses of the same university would be even easier. It is very probable that funding and resources can be more easily shared and that graduate students will have even an easier time working in such collaboration. I see nothing that would impede collaboration here.
I have worked with a national lab (which, although not a university, can at least somewhat resemble academia a little bit) that had two locations. We collaborated commonly between campuses. It made funding considerations quite simple and we produced quality research.