SANRAL and Trans African Concessions (TRAC) have a long-standing partnership to maintain and improve the quality of the N4. At least 168 SMMEs have been contracted to work on N4 road rehabilitation and upgrade projects currently under way, including the Belfast-Machadodorp section, amounting to R380 million worth of subcontracts. The N4 saw a 214% increase in total traffic on the South African side from 2001 to 2019.