There is a new field on the Personal Details page of your Profile page where you can input your vehicle type and have it show under your avatar in posts.
Yeah, that's not gonna show up on the phone under the avatar. There's no hardly any screen real estate on the phone to deal with as it is. It will show up under the avatar when using the full Web browser (either on the phone (in landscape mode) or on the computer).
In addition to Vehicle on the Personal Details setting page, there is a new Expediter Type where you can select among Driver, Owner/Operator and Fleet Owner. If you select one of those, it will create the appropriate banner for it under your avatar.