Abstract: An improved wheel end valve assembly (11A) for a central tire inflation system (10) having a single connection (68) to a tire chamber (74) and a single supply connection (62) to a source ( 142) of pressurized fluid, which requires no venting other than through the single supply connection (62), is effective in response to pressurization and venting of the single supply connection (62) to open and close communication to the tire chamber (74), and which is not affected by ambient temperature changes nor susceptible to leakage into and out of a trapped air volume employed by prior art valve (11) disclosed herein. The valve (11A) is actuated by air pressure and is resiliently biased into closed position by a spring (342) positioned within an evacuated bellows (334).