Two dimensional deuterium NMR measurements are reported for three different onium salts (CH3)3SeNO3-d3, (CH3)3TeI-d3, and (CH3)3SI-d9. In these molecular solids with the general structure (CH3)3E+X-, three methyl groups are attached to the E atom. There is the possibility of reorientation of the methyls about their C3axes and reorientation of the whole tri-methyl group about the C'3axis. From an analysis of the 2D NMR exchange spectra the angle between the E-C bonds and the rotation axis for trimethyl reorientation were determined. Exchange rates and spin lattice relaxation times are given for several temperatures, to show how the mixing times for the experiments were selected. The data presented for (CH3)3TeI-d3, demonstrate that 2D techniques are sensitive to motions on a time scale an order of magnitude slower than that accessible using 1D line shape techniques.Key words: deuterium NMR, molecular motion, onium salts, two dimensional spectra.