Experimental data on frequency-temperature relationships tan delta(t, f) for diesel fuel (DF) and the diesel containing the pour-point depressant Dodiflow-4971 (DDF) and C-10-C-18 higher fatty alcohols (HFA) are presented. The tan delta (t, f) relationships have been obtained in the frequency range of f = 0.025-1000 kHz at temperatures (t) ranging from -40 to +100A degrees C. For the diesel and the DF + DDF, DF + HFA, and DF + DDF + HFA systems, two temperature regions of dispersion of tan delta have been revealed, the high-temperature region from 60 to 8A degrees C and the low-temperature region from 19 to -40A degrees C. Based on the ratio of dielectric loss tangent in the interval of the colloidally dispersed state of the diesel doped with additives (Adi) to that of the additive-free diesel fuel, , an indicator of additive dewaxing performance (IADP) has been proposed, which makes it possible to predict the performance of the additives as activators of the diesel dewaxing process in an electric field.