Before using specialized tools, try common default codes such as 0000 , 1234 , or the last 4 to 6 digits of the vehicle's VIN (both forwards and backwards) .
However, if you run a professional shop working on 2018+ trucks, the "MHH way" is risky. The time lost fighting malware and bricked ECMs usually costs more than just buying a legitimate subscription for $1,200/year, which includes unlimited legal data unlocks. mhh auto cummins insite data unlock best