"A car is a depreciating asset? Now I've heard everything!"
As far as a companies balance sheet accounts go a car is a depreciating asset, and if you were to approach a bank it would also be deemed an asset.
That being said cars loose value the second you purchase them, they derive no increase in value (unless a collectors item, and cost money to maintain and operate whilst generating no income, thus there is also an argument they be deemed an expense.