I wonder if Holden/GM will offer a settlement at the door of the courtroom? “We fit a new LS3 to your car, just sign this confidentially agreement“?
Such issues have been addressd by ACL and clarified by ACCC
Consumer guarantees
Your statutory rights that cannot be replaced, limited or removed by any agreement, contract or warranty, or made subject to non-disclosure conditions.
If something goes wrong with your new car, you may be entitled to a remedy under the consumer guarantees as well as the manufacturer's warranty or any extended warranty you might have.
www.accc.gov.au
However, it wasn't unheard off for such agreements to be signed...
Heck, I'd sign, knowing they are somewhat questionable and in fact legally unenforcable
Non-disclosure agreements
A non-disclosure agreement (also known as a confidentiality agreement) is a legal contract between two or more parties that prevents the disclosure of certain information to an outside party.
A non-disclosure agreement may be used to settle a dispute between a consumer and a person or a business, so that both sides can achieve a result without having to go to court or tribunal.
:
"Consumers who raise a complaint about a product or service may be asked by the trader to sign a non-disclosure agreement, in order to receive a replacement, refund or compensation, and settle the dispute. It is not compulsory for the consumer to sign a non-disclosure agreement."
From 28 February 2019, a non-disclosure agreement cannot limit a consumer’s ability to lodge a complaint with NSW Fair Trading. Any such terms in a non-disclosure agreement will be void and not legally enforceable.
Before or at the time of asking a consumer to enter into a non-disclosure agreement, the law requires that the trader inform the consumer of their ongoing right to lodge a complaint with Fair Trading.
If a trader fails to inform a consumer of their ongoing right to lodge a complaint with Fair Trading, the law provides for maximum penalties of $22,000 for offences by corporations or $4,400 in any other case.
Information about entering a contract, non-disclosure agreements, consumer and business rights and responsibilities.
www.fairtrading.nsw.gov.au