Used passenger-car sales in June were the strongest for the month for nine years, driven by continued consumer confidence and a speeding domestic economy.
Motor Trade Association figures showed more than 10,000 used passenger vehicles were sold last month.
And for the first half of the year sales were the strongest since 2006, with the Nissan Tiida, Suzuki Swift and Mazda Axela the most popular models.
MTA dealer services and mediation manager Tony Everett said the strong first half showed the current spike in vehicle sales was a sustained trend rather than "short-term exuberance".
But new commercial and passenger car sales also continued to rev in June.
New commercial-vehicle sales were the strongest on record and the highest overall for the first six months of a year as well.
"June is historically a big month for commercial vehicles due to Fieldays, but this is exceptional," Everett said.
New passenger cars sold at the highest number for June in 25 years, and were a record for the first six months of the year.
The strong sales for the first half of the year across all sectors indicated a buoyant domestic market, driven by strong consumer confidence, Everett said.
Toyota's Rav4, Corolla and Highlander were the top-selling passenger vehicles during June.
But motorcycles were also up 14 per cent on the same period a year ago, led by Suzuki and Honda.
"This is surprising, given we're heading into the teeth of winter," Everett said.
"Scooters haven't been moving, which is a bit of a surprise - there is a long-established correlation between high fuel prices and booms in small, step-through motorcycles."
Diesel prices fell by 2 cents a litre last week, the second time in a week, but petrol remained flat after a 3c rise on Tuesday because of an excise tax increase.
A litre of 91 octane is 223.9c, while diesel has fallen to 149.9c.
- The Dominion Post