Abstract: A substantially conventional tubeless or tube-type tire casing is mounted on a wheel and contains a centrifugally distributed solid elastic fill material which is deflation proof. A heat curable elastomer is injected into the casing in liquid form, the casing is pneumatically pressurized to seat upon the wheel rims, and the assembly is rotated to centrifugally distribute and position the liquid elastomer until it has cured. Alternatively, a pressurizable tube of relatively small diameter extends about the wheel within the casing and between the beads and rims of the casing and wheel. The tube is belted to limit its radially outward expansion and is filled with air at a pressure sufficient to securely hold the casing beads on the wheel rims. The elastic fill material may have characteristics providing a ride equivalent to a relatively low air pressure and at the same time, the casing will be securely locked to the wheel by relatively high pressure in the belted tube.