In the present work, the experimental L-i (i = 1-3) sub-shell fluorescence (omega(1), omega(2), omega(3)) and Coster-Kronig (f(12), f(13), f(23)) yields for W and Re have been deduced from synchrotron radiation induced X-ray line intensities measured at different incident energies across the L-i absorption edge energies of both the elements employing two sets of photoionization cross sections based on the non-relativistic Hartree-Fock-Slater model and the self-consistent Dirac-Hartree-Fock model. These deduced yields have been compared with the Dirac-Hartree-Slater model based theoretical values, the semi-empirical values tabulated by Krause and the recommended values tabulated by Campbell. The present investigation provided reliable experimental evidence indicating the onset of intense L-1-L3M5 Coster-Kronig transition at Z = 75.