A quick look at the asic website suggests they were wound up by one of their suppliers?
Yep, and sadly it looks like they had been in serious financial strife from early this year at least, including being evicted from their rented factory premises.
To the point that the liquidator regards the transfer of Greenfield's records/assets to Cox Industries as of doubtful legitimacy, and has taken Federal Court action to recover them...
http://www.judgments.fedcourt.gov.au/judgments/Judgments/fca/single/2018/2018fca1252Very sad indeed, that an iconic Aussie mower manufacturer should come to such a messy demise.