Classical limits of the quantal centrifugal-sudden approximation to generalized cross-sections have been derived and compared with the exact classical results. Detailed comparisons between the classical centrifugal-sudden approximation (cCSA) values, the exact classical trajectory results, and the corresponding quantal calculations are then carried out for the Ar-N2 system, and contrasted with Similar comparisons for He-N 2. Above 150 K the cCSA is found to be accurate to within 1% for the temperature dependent viscosity and diffusion cross-sections and 5% for the viscomagnetic and depolarized Rayleigb lightscattering cross-sections.