Board Thread:Social and Race Teams Threads/@comment-25956839-20180326200658/@comment-2601:601:8300:3944:D936:4EF:5D7F:DEE5-20180327044334

Usually you  can find the 'car(s) that can be used in the challenge' info listed above. ^^^

I interpret "All cars" to mean any car that is in your stable...no buses, no monster trucks, no bicycles...but I'm just guessin'