The trucking industry says many operators are being driven out of business because of the economic downturn.
According to the latest business confidence survey by the Bank of New Zealand, transport volumes are patchy and revenue is down.
A net 2% of the 540 respondents expect the economy to improve in the next year, compared with 26% in June.
The Road Transport Forum says that while the price of diesel has dropped, and companies have been slashing other costs where possible, margins are very tight.
Chief executive Ken Shirley says the road ahead looks bumpy, with road user charges under review, increases in ACC levies and the emissions trading scheme which came into effect on 1 July.