Question The maximum width for any vehicle is: Answers 3 feet. 7 feet, 9 inches. 8 feet, 6 inches. 12 feet. Explanation In Illinois, a vehicle may be no more than 8 feet, 6 inches in width. There are specific exceptions to this rule for certain farm equipment and buses. Take a FREE Practice Test Now This questions appears in the following tests: Illinois Knowledge Test Class A ,