In one aspect, a system for monitoring frame levelness of an agricultural implement may include first and second sensors configured to detect first and second parameters indicative of forces exerted on first and second ground engaging tools of the implement by the ground, respectively. The system may also include a controller configured to monitor a parameter differential between the first and second parameters based on measurement signals received from the first and second sensors, with the monitored parameter differential being indicative of at least one of pitch or roll of a frame of the implement. The controller may be further configured initiate a control action associated with adjusting the pitch and/or the roll of the frame based on a magnitude of the monitored parameter differential to adjust an orientation of the frame relative to the ground.
