Ricky Muir has used his inaugural speech to mount a passionate defence of penalty rates, describing what it's like to lose sleep when the cost of living rises by $20 a week.

The Australian Motoring Enthusiast, who was elected to Parliament on a miniscule primary vote that was boosted by a favourable preferences deal, defended the current electoral system from attack by the major parties and said he would fight to prevent the 4WD and car culture being "legislated out of existence".

Senator Muir has spent eight months in the Senate before delivering his first speech – thought to be a record - but when it came it was warm and self-deprecating.

He thanked veteran TV host Mike Willesee for the train wreck interview in which he failed in numerous attempts to explain what the automotive aftermarket is.

He said Willesee had taught him a lesson: "Just to be myself".

That person, he said, was a rural Victorian family man who had spent a childhood "below the poverty line" but dreamed of leaving school at age 16 and getting straight into manual work, most recently a timber mill worker.

"I wanted to work in earth-moving or on a farm, in manufacturing, a factory, as a mechanic, with tools, wear stubbies, hi-vis and have the constant pale shade of a singlet embedded on my otherwise tanned skin," he said.

But the working life came with the challenge of surviving in working class Australia.

"I have a long history of living at the receiving end of legislative changes, of feeling the squeeze of new, or higher taxes, feeling the pressure and even losing sleep when you realise that the general cost of living just went up a tiny $20 dollars a week. To everyone sitting in this chamber, if you think $20 a week is nothing, or just a pack of cigarettes and or a few beers, you have never lived in the real world," he said.

"I have been the beneficiary of penalty rates. I worked shift work and weekends not for the love of the job but because there was financial incentive to do so.

"This is called disposable cash and in my case this was spent on hobbies such as riding dirt bikes with my wife and children, buying camping supplies as it was an inexpensive way for us to go on holidays, maintaining my 4x4 and competing in affordable grass roots motorsport.

"That disposable cash ended supporting Australian manufacturers in the aftermarket industry, local businesses, communities and retailers helping create and maintain Australian jobs."

The Coalition has tasked the Productivity Commission with reviewing workplace conditions and it will consider penalty rates.

Senator Muir said he had been "fed up" with the two-party system when he decided to stand for election but vowed not be an obstructionist in the Senate and denied that the Senate was "dysfunctional and unworkable".

But he delivered a warning to the major parties to leave alone the system which has enabled micro-party candidates like him to join the crossbench on the back of preference deals.

"There has been plenty of commentary of how the voting system is broken and un-democratic which in my eyes completely misses the point. For my crossbench colleagues and I to be elected, people had to be voting for parties other than the major parties, and they did. A huge 24 per cent in the Senate … the system is not broken, and does not need to be fixed," he said.

Senator Muir paid tribute to his wife Kerri-Anne and five children who were in the gallery to watch his inaugural speech.

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