What you haven’t told me, Luke, is whether your car has a petrol four-cylinder engine or a V6 turbo-diesel. In any case, the petrol engine fitted to this series of A5 Audis used a timing chain, so it should never need replacing as it’s designed to last the life of the engine itself. That, however, has not been the experience of every owner of these cars, and timing-chain failures have been a hot topic of discussion on these four-cylinder turbocharged engines.

The V6 turbo-diesel, however, does use a toothed rubber timing belt, and that, along with its tensioners, does need to be changed at regular intervals. The trade reckons that interval should be every 120,000km or every five years, whichever comes first. That’s because rubber deteriorates with time as well as kilometres. The other piece of advice is to change your water pump while you have that part of the engine pulled apart. It’s a lot cheaper to do both jobs in one go than to open the engine a second time to replace the water pump.
 

There’s good and bad news here, John. The transmission in the car you’re looking at is code-named DL501 and it’s a wet-clutch design. That’s distinct from some of the dry-clutch designs also used by the VW Group which were much more troublesome with a high rate of failures. That’s the good news.

The bad news is that even with its more durable wet-clutch design, the DL501 has also been known to suffer what appear to be inherent problems. Mainly, those relate to the mechatronic unit (more or less the transmission’s central nervous system) and premature wear in the clutch plates themselves.

The car you’re looking at has covered a very low distance, so it should be okay for now, but there’s no telling what dramas might crop up with years and kilometres. The problems will likely be worse if the car has not been serviced by the book, so check the service handbook for evidence of this. Even then, it’s a bit of a gamble.

But the only thing I’d stay further clear of than a DSG transmission would be an extended warranty from a car-yard. These are specifically written to exclude the things you’re most likely to need them for. Have a close look at the fine print and you might find that the sort of transmission problems you’d expect in this car will be specifically excluded.

Both the petrol and diesel versions of Audi’s V6 are high-performance units that will provide all the performance you’ll ever need. But for most people buying an A5, there’s really only one that’s the right engine for them and it has nothing to do with reliability.

The turbo-diesel V6 is only really happy if you’re regularly using it for longer journeys where the engine gets hot enough to regenerate its soot-filter. This isn’t an Audi-specific thing; it applies across the board to all modern, common-rail diesel engines with soot-filters. For most urban-dwelling Australians, the pattern of vehicle usage doesn’t include those critical long journeys at freeway speeds, and driving around the suburbs for 12 months without a regular gallop on the open road will almost guarantee problems with the diesel’s emissions control systems (including the soot-filter).

Which means that for the vast majority of A5 buyers, the petrol V6 is the only way to go. While you will be losing a little fuel economy over the diesel, the petrol V6 is actually a nicer engine to use and live with. It’s faster, smoother and definitely more refined. And you won’t smell like a semi-trailer every time you fill up.