How many license plates must a truck tractor display? Do you currently have car insurance? Insurance is mandatory to drive in Ohio Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question How many license plates must a truck tractor display? Answers One Two Three Four Explanation Unless registered under the International Registration Plan (IRP), most vehicles are required to display front and rear license plates. Truck tractors must display one plate on the front. This questions appears in the following tests: Illinois Class B Knowledge Test