Hi there, daniel-millen.
Let me share with you what I know about the feature that you're referring
QBO Desktop app was already discontinued due to some updates. To keep track of your miles, you can use a mobile app.
Let me provide you the steps on how to track mileage thtough mobile app.
- Open the QuickBooks mobile app.
- Select the menu ☰ icon and then Mileage.
- Choose Auto-tracking.
- Click Manage Vehicles.
- Enter the vehicle.
- Select the Set as primary vehicle toggle.
- Select Save.
For additional information you can check this article about mileage: Automatically track mileage in QuickBooks Online
I'll also be adding these article for future help:
Know that you can always get back to me if you need anything else. Have a nice day!