A snowmobile chassis includes dual panels that form a lighter weight and stronger tunnel preferably without the need for structural doublers, plates or other attachable reinforcement devices. The dual panels take the form of inner and outer panels coupled together with selective gaps or spaces located between the panels. The gaps laterally separate the panels and may be continuous and take a variety of shapes as defined by each panel's configuration. The arrangement of the gaps may advantageously define a desired structural load path through the tunnel, increase a section modulus with respect to a centerline of the tunnel, and reduce an overall weight of the tunnel as compared with conventional tunnels that utilize added reinforcement devices.