As with other QuickBooks list items, if a vehicle is in use somewhere within
your company file, such as, if it has an associated mileage record, you cannot
delete it from the list. However, you can make the vehicle inactive so that it
won't show up in the list or on any mileage reports.
Go to the Company menu and click Enter Vehicle Mileage.
Click Vehicle List.
Select the vehicle.
Click the Vehicle button and choose Make
To see the vehicle in the list again, select the Include
inactive checkbox at the bottom of the Vehicle List window.
Go to the Edit menu and click Delete.
Important: If you delete an entry by mistake, immediately go to the Edit menu and choose Undo Delete.