A tubeless pneumatic tire/fluid reservoir assembly capable of being mounted upon a standard drop-center rim without deviation from standard mounting procedures for the tire alone. The tire contains an anchoring device comprising a reinforced strip having a first portion bonded and/or integral with the innerliner of the tire and a second portion that is affixed to the fluid reservoir. The fluid reservoir includes a hollow arcuate body capable of containing a fluid under pressure and capable of discharging same under coexisting predetermined conditions of pressure differential and temperature.