What is the ruling on purchasing a car in installments from a bank that owns it and keeps it in its lot, knowing that no additional dues are incurred in case of failure to pay the monthly installment?

If the bank owns the car, it is permissible to purchase it from them either with cash or in installments, even if the installment price is higher than the cash price. This is because time has a share in the price, and this is what the rules of Sharia necessitate.