Abstract: A wheel retainer for the safety of all motor vehicles, and more particularly for trucks of all types, to prevent wheels or wheel assemblies from flying off moving vehicles in the event of axle breakage or other mechanical failure which would cause a wheel or wheel assembly to fly off. The wheel retainer includes brackets for attachment to a truck frame and a retaining bar which is removably attached to the brackets, the bar and brackets being positioned to prevent the wheel or wheel assembly from flying off of the vehicle. In a further modification of the wheel retainer, a loose wheel indicator is provided. The loose wheel indicator is mounted to a turnable or steerable wheel or wheel assembly such as a front wheel of a vehicle. The loose wheel indicator causes an audible noise, audible to the vehicle driver, by contact created between the indicator assembly and the rim of a tire when the wheel or wheel assembly comes loose thereby warning the driver of the loose wheel hazard.