"Kept one's shoulder to the wheel" is a phrase that describes the act of persistently working hard towards a goal or objective without giving up. There are several other words or phrases that can be used as synonyms for this phrase. A few examples of such phrases might include "pushed through", "persevered", "maintained focus", and "stuck it out". Alternatively, words such as "dedication", "diligence", "determination", and "tenacity" could also be used to describe this sense of persistent effort and work ethic. Ultimately, the key idea behind this phrase and its synonyms is that the individual in question did not shy away from the challenges or obstacles they faced along the way, but instead tackled them head-on and refused to give up or give in.