Nonequilibrium carrier dynamics was studied in undoped and vanadium-doped 6H-SiC wafers by using photoluminescence spectroscopy and light-induced transient grating (LITG) technique that was shown to be more informative for wafer characterization. Carrier recombination time of 400+/-10 ps and diffusion coefficient of 2.7+/-0.2 cm(2)s(-1) were extracted for the undoped sample by using LITG technique. The corresponding parameters for the V-doped wafer were approximately 3 times lower than those for the unintentionally doped wafer (130+/-5 ps and 1.0+/-0.5 cm(2)s(-1), respectively). The V-doped wafer exhibited a non-uniform distribution of carrier lifetimes in the range of 10% on the millimeter scale. The obtained results demonstrate potential of the LITG technique for contactless carrier lifetime evaluation in SiC wafers and allow establishing the effect of vanadium doping on material parameters of SiC substrates.