I don't think anybody these days considers less than seven years and just over 100,000km to be the lifespan of a modern engine. Certainly not in a car serviced properly. And since this is a known problem with these engines, I think you have a very good case for Hyundai to at least help out with the repairs on a pro-rata basis.

Our experience lately has been that some Hyundai dealerships have been ignoring cases like these and not giving them the consideration they perhaps should be. In any case, any decision to help out with repairs must come from head office, so I'd forget about the dealership for now and go straight to the top. Hyundai Australia has a customer service division and that's who you need to be talking to. Approaching the ACCC should be your last resort, but at least give Hyundai the chance to do the right thing by a loyal customer.

Hyundai’s Theta 2 family of engines does, indeed, have a pretty chequered track record for reliability. But it’s important to note that the majority of vehicles affected have been US-market cars with engines built in a different factory to the cars supplied to Hyundai Australia. For the record, the North American cars in question experienced debris from the engine machining process blocking the oil passages inside the engine, leading to bearing failure. In some cases, the engine failure resulted in a roadside fire.

Even though our iX35s were built in South Korea rather than North America, there’s still a chance the same problem could crop up here given that engineering materials and techniques tend to be standardised across all factories in the name of efficiency.

As you point out, your car is now out of warranty, but I wouldn’t leave it at that. I’d be talking to Hyundai’s customer service department with a view to at least getting some assistance in having the car fixed if, indeed, it was a manufacturing fault that caused the engine failure. I’d also be pointing out that 80,000km is not a realistic life expectancy for a modern engine. To get anywhere with this approach, you’ll need to be able to show that the car has been serviced by the book and (probably) that the failure was due to a loss of oil pressure that led to bearing failure.

Anything can be made to work if you throw enough money at it, but the short answer, Bassel, is no. For the 2014 model year, Hyundai upgraded the petrol engines in the iX35, and the two-litre unit in your car received a direct-injection fuel system. While the basic engine architecture might be the same and the engine would probably physically bolt in, it’s almost certain that the computer in your car would be incapable of controlling the direct fuel-injection function. Your car is also probably missing components such as wiring, a high-pressure fuel pump and sensors required to make the newer engine operate.

You could also run afoul of the authorities because the earlier engine you want to use had a (slightly) higher tailpipe emissions rating. Our regulators take a fairly dim view of a vehicle being modified and going backwards on emissions.