I am not exactly sure I follow what the issue is but I think you are having a issue with the vacuum system on the vehicle?
The hubs on this vehicle are what are called Integrated wheel end system and basically they are applied with vacuum.
See below for more detail on how this works.
Also, if you are having an issue with this, the best way to find the issue is test the connections with a vacuum pump to see if you have a line issue or something else in the system.
Here is a guide that will help with the pump that I am talking about:
https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
If the hand pump cannot operate the system then you have a line issue most likely.
Please clarify what you are seeing and then let us know if this is what you are dealing with.
Thanks
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Friday, September 24th, 2021 AT 3:01 PM