Data from several Voyager 1 experiments are used to determine the magnitude and L dependence of the radial diffusion coefficient for low-energy charged particles outside fo Io's orbit under steady-state conditions. The extreme ultraviolet observations near 685¿ are inverted to produce an ion density profile for L>6. This normalized ion profile, as well as the (equatorial) electron density profile estimated from the planetary radio astronomy (PRA) observations falls off as L-5. Such a density gradient would make possible centrifugally driven cross-L diffusion outside of Io's orbit without ruling out the presence of an atmospherically driven mechanism. A lower limit for the radial diffusion coefficient DLL is 1.5¿10-10 L5 RJ2 sec-1, yielding a characteristic diffusion time from 6RJ to 7RJ of less than 10 days, much shorter than previously anticipated. Steady-state diffusion is not a good assumption inside of Io's orbit, where the particle densities decrease sharply from 6RJ to 5RJ; the diffusion time in that region is probably longer than outside of Io's orbit.