This study demonstrates the efficiency of 13 C- C TOCSY mixing via the DIPSI-3 mixing sequence for sensitivity-enhanced solid-state NMR experiments. 90 degree pulses before and after the DIPSI-3 mixing sequence are important to prevent unwanted cross-transfers resulting in mirrored peaks and loss of sensitivity. The methodology can be seamlessly integrated with advanced sensitivityenhanced mixing sequences, such as TROP and SPEPS, which facilitate transfers between backbone atoms. Consequently, it enables the construction of sensitivity-enhanced 4D experiments, thereby facilitating the side-chain assignments of complex membrane proteins. We validated this approach using a back-exchanged perdeuterated protein sample of the full length 30 kDa membrane protein GlpG. A comprehensive dataset, suitable for backbone and side-chain assignments, comprising two double sensitivity-enhanced 3D spectra and four triple sensitivity-enhanced 4D spectra was acquired within a three-week period at 55 kHz MAS on a 600 MHz spectrometer. Interestingly, despite utilizing a back-exchanged perdeuterated sample, all anticipated side-chain carbons for all residue types, excluding the C and C of isoleucines and leucines and the C of lysines, were detectable. This approach should prove even more advantageous for proteins with higher degrees of side-chain protonation that enables more efficient 1 H- C magnetization transfers compared to back-exchanged perdeuterated samples, provided that sufficiently fast MAS rates and/or high external magnetic field strengths are applied.