Warrant of fitness inspections for older cars could be conducted annually, rather than every six months, under reforms being considered by the Government.
Vehicle registration will also be reviewed, which Transport Minister Gerry Brownlee says could save households and businesses millions of dollars each year.
Some 5.5 million warrant of fitness inspections are carried out each year costing car owners about $250 million.
The Motor Trade Association, which represents mechanics, says annual warrant inspections would allow vehicle faults to go undetected for longer.
Vehicle Testing New Zealand says warrant inspections every six months may well have contributed to the declining road toll and a reduction in the number of accidents.
It says if inspections are conducted annually they would need to be more rigorous.