Your Challenger won't drive? You're probably in the passenger seat.
Can't sell/delete an item? Check all of your loadouts, it's likely still equipped.
Auction house? Why? It'll just render bits purchased lock boxes pointless, and weapons are mostly equal anyway.
Gear/enemy progression? No thanks, it'll only render 90% of the content trivial when you reach the highest zone.
If you are doing the main storyline missions, for a short time you can get the larger truck at the start and then a similar one later farther down the map in the storyline missions as well. They only last for you until you've completed those missions. After that you lose it.