MKS38 explained how to setup the required data for load planning relevant resources correctly. As it would be a bit annoying to maintain this data for each single resource seperately, SAP TM comes with vehicle types. They cover all required information and can be assigned to a resource when creating it.
You can find vehicle types as a subset in the TM customizing under Master Data->Resources->Define Equipement Groups and Equipement Types.
As a specific equipement vehicle groups are available as subset. On the right side you see the attributes also available in the resource itself.
In the resource viewer the vehicle types are displayed:
When creating the resource, a field to enter the vehicle types is available:
After entering that, the attributes are automatically taken over. Afterwards they can be overwritten if required and saved.
From my point of view a good way to simplify the load planning master data.