Analysts believe Mr Swarbick, who has resigned from the group with immediate effect, has paid the penalty for the poor performance of its plant hire business.
"He was responsible for day-to-day operations, some of which have performed and some of which haven't. It is reasonable to assume that these problems are not unrelated to his departure," said Neil Stothard, Vibroplant's finance director, who joined the group three weeks ago, replacing Eric Woolley, who left in May.
Mr Swarbick was on a one-year contract and earned pounds 67,500 last year. Vibroplant refused to comment on whether he would be entitled to compensation.
Vibroplant insists the management shake-out is over but many more employees could still lose their jobs.
The company has embarked on a costly reorganisation of its plant hire business aimed at centralising its depot system.
It has just announced two depots will be closed and several more will follow around the country as it attempts to put itself back on a firm financial footing.
Mr Swarbick's exit leaves just four people on Vibroplant's board, including the chairman and chief executive, Jeremy Pilkington, Mr Stothard and two non-executive directors. But Mr Pilkington could soon split his role and appoint a new chief executive to conform with Cadbury recommendations on corporate governance.
John Tull, a former managing director of Alfred McAlpine's plant division, will take over the management of the plant hire business.
Vibroplant, which lost pounds 2.9m in the year to March, has been hit by a weak construction market and government road building cuts.