A Torque Converter should be a life of vehicle component (or a long lived component that should last much much longer than 81,000kms if the lock up clutch control algorithm correctly handles slip and heat build up). IIRC there was an issue with 6L80E TC were a manufacturing fault in a batch of vehicles caused a cracked snout and vibrations. Sadly Holden didn't address this known product defect via recall. Maybe someone can point to a service bulletin that quantifies the TC issue...
Luckily Australian Consumer Law requires products sold within Australia to be fit for all the purposes for which goods of that kind are commonly supplied, acceptable in appearance and finish, free from defects, safe and durable. Also of relevance is that the the law doesn't specify an end date for such requirements (like a manufacturers voluntary warranty does)...
In this instance, I'd say the dealer that sold you a car has failed to meet their legal obligations to provide a vehcile free from defect, safe and durable as required under ACL, even after 81,000kms and 8 years...
Best to read up on ACL and your statutory warranty rights so you can get some background on the subject. I've made many comments that contain extracts, links and references to ACL within the
Sudden Loss of Power Steering WHEN DRIVING thread so jump into that and read.
Then when you've got more of a handle on the law, ring the QLD Office of Fair Trading and have a chat to them about your problem. They'll be able to direct you on the best way forward. After you understand your rights, go back to the selling dealer and have a talk with them and let them know you want this defect corrected under your ACL statutory at no cost to you... Maybe they'll understand they can't pull the wool over your eyes any longer and you *and them) may avoid ending up in QCAT
Just remember, with ACL, it's the selling dealer's issue to resolve. You shouldn't concern yourself with Holden (the manufacturer who built the car) or their voluntary warranty and it's length and expiry date.... such is a back office issue for the dealer to recoupe its loss on the defective product they sold. So ACL should have you covered (though you may have to fight for it)
PS: Why has Holden hidden this issue and is not helping customers? Well they shafted their customers and dealer network when they announced Holden's closure, because big knobs in Detroit cared more for their bonuses and US auto union than us peasants down under
