I'm thinking they're probably the e-Bearing hubs. They have proven to not be as reliable as OEM - or even used OEM - hubs.
Several racers have "killed" those hubs. They may be okay for street cars, though.
(If anyone has a different opinion, please feel free to jump in. No skin off my back.
If your hubs turn smoothly, with no vibration or noise, I would be inclined to leave them alone.
[This message has been edited by Raydar (edited 03-31-2018).]