A man with 45 years' experience as a mechanic thinks tampering with rules on warrants of fitness could cause loss of life.
Under proposals announced on Tuesday, the Government could reduce warrant of fitness checks to once a year for cars under 12 years old.
It is one of several proposals unveiled for debate as the Government looks to save money.
Don Sweet told Radio New Zealand's Nine to Noon programme on Thursday he believes he has saved thousands of lives by doing six-monthly inspections.
"When you talk about the repairs, I've found steering joints falling off, brakes worn right out, brake hoses cracked to bursting, rusted brake pipes, tyres with steel cords coming out.
"And that's not just on six-month checks, that's on one-year cars as well. I just think the six months is going to save lives."
Associate Minister of Transport Simon Bridges says any changes to the system would have to achieve similar safety outcomes or improve on them.
Submissions close at the end of October.
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