There wasn't the same division of civil and military government in the mongol system, or even civilian institutions as we'd understand them today. The mongol empire ran in large part on "loyalty networks", where subordinates would be personally loyal to their patron specifically, not any office they held [1]. Powerful people wouldn't assume loyalty, they'd be constantly engaged in building and maintaining the loyalty of their subordinates in order to maintain their own power. If this sounds like it'd lead to dynamic systems of government full of infighting, indeed it did. That was part of the enduring success of Central Asian polities and broadly similar to e.g. Europe.

[1] Small caveat on this in that royal families held something akin to the mandate of heaven by virtue of their heredity. This mandate did not necessarily follow lineal descent and regularly transferred to siblings, family, or even close vassals that outshone than the original line.