I don't know about our vehicle specifically but, with some engine designs, the oil routes as follows:
* pan/sump to pump
* pump to filter
* filter to diverter
* diverter-primarily flows to engine
* diverter-partially to oil cooler
* oil cooler to engine
We also have a turbo that needs lubrication and cooling so I'm not sure where/how that ties in. I mean, is it 100% supplied from the oil cooler?
Our oil cooler is an oil/coolant heat exchanger. Some older designs run the oil out to a radiator as if it were automatic transmission fluid, but that is not ours.