I have a Q7 3.0 TDI (2012) and a 2013 Cayenne TDI (same engine?).
What long term service is required or recommended? Say 150k, 200k miles?
On the gas engine (particualrly the 2.0T), the notorious timing chain service is a common issue. Does the 3.0TDI also have the need for timing chain service?
Other major service items (aside from oil, filter, fuel filter changes) that I should consider and check on?

 

A full fluid change (brake fluid, coolant, transmission fluids including the mechatronics one, transfer case and differential fluids)

Inspect and fix the suspension in case you haven't done this recently.

The timing chain gets replaced every 80-120k miles so depending on your mileage and prior service history, one or the other might be due for replacement.

One thing you really must do for timing chain extended life is avoid the standard Audi advice of topping up oil every time you lose some between changes. If you lose a quart or more of oil and aren't yet due for a change, no worries - just spend the 180-200 extra and drain + refill the engine oil. Works out far cheaper long term than timing chain replacement, premature engine wear and so on - and potentially your chain remains good for the life of your engine.

 

Is that Audi saying or your personal opinion?

 

So what you in effect are saying is: change oil LONG before the manuacturers RECOMMENED interval (that is what those companies base their warranties on, and bet a lot of money on it). Allmost sounds like those hillbillies that still swear you must change oil every 3000 miles (like they did on their farm tractors/pickup trucks a half century ago).

 

What I’m saying in effect is that the various Audi fora wouldn’t be full of people griping about their engines consuming oil or oil wear indicators lighting up so they have to keep going in for top ups, if they changed oil when the indicator shows a quart or more lost or oil wear indicators lighting up, rather than just adding a quart topup

Of course by the time this begins to matter, your car will be well out of warranty and thus begin the litany of posts about needing piston soaks, excessive oil consumption and so on.

 

Also consider, if you will, that the timing chain is lubricated by the engine oil, and long use of even the robust vw spec oils (a 504/507 oil in your case is over and above what acea c3 requires) makes it shear down and leave various parts of your engine, including the timing chain, vulnerable to wear.

That old folk wisdom about 3000 mile oil changes came during times when all the oils used were conventional and mono weight. Modern oils are manufactured with detergents and other additives and have a much longer drain interval but that is considerably reduced under “severe service” like towing, off road use and, what a surprise, short trips in bumper to bumper city traffic. Most car manuals have fine print recommending that you halve the oil change interval in such cases.

Here is Audi’s version, which just adds an “etc” in, for example, a 2019 maintenance chart

https://static.nhtsa.gov/odi/tsbs/20...69091-0001.pdf

.

 

So IF severe condition apply, reduced oil change intervals are recommended. And if NOT, why would I drain 6 or more perfectly good quarts of oil out if service is NOT due instead of adding a quart of fresh oil and keep going until service is due?

10,000 is normal service:
at 5,000 mile I add a quart
change at 10,000 (consumed 9 quart oil change plus 1 quart, one filter)

Or

at 5,000 miles (one quart low) dump 8 quart
fill 9 quart
at 10,000, dump 8 quart
fill 9 quart
used 18 quart and 2 filter

I think you should change oil when it is NEEDED, i.e. 10k for normal operation or reduced, depending on severeness of us, maybe as low as 5k if all is towing or short distance.

 

Back to the real question:
- chain clatter seem to be an indicatore (chain tensioner on its way out, not working as it should anymore)
- expect 300,000 of chain live
- change right away if chain clatter is noticable AND chain is not tight (don't know how to easily check).

 

The chain typically lasts the life of the engine and is lubed by the engine oil.

If you lose a quart out of what is it, 7 quarts, that is a seventh of your oil gone and the rest of the oil in a somewhat suspect condition. Oil loss just isn’t normal in a crdi engine and shouldn’t be normalised by any manufacturer, so this “oh just add a quart” isn’t conducive to engine life, especially when the engine runs hotter than most others for efficiency.

Yes chain clatter is likely an indication of wear or the chain slackening. As is engine misfiring, metal shavings turning up in your oil etc for severe cases.

Shortens the engine life and is much more expensive than cheaping out by adding a quart top up instead of spending max a couple of hundred dollars on new oil and a filter.

To be serious, you keep your cars for a long period if you’re asking about 2012 vehicles. Audi or any other car manufacturer’s service recommendations are more geared towards ensuring your car remains trouble free .. till the warranty lasts, and the uncharitable would say, provide a sizeable revenue stream for dealerships in the years after, with water pump, premature timing chain wear etc issues becoming “famous”, all of which depend for a long life on engine oil not being excessively worn or lost.

This is an interview with a former Nissan GTR senior engineer where he has some advice you termed hillbilly folk wisdom in another reply. I would encourage you to watch this before you next top oil up when you lose a whole quart (which is somewhat like closing the barn door after the horse has bolted)

 

Our ‘10 Touareg 3.0 tdi just hit 227,000 miles.

No chain rattle on the original chains.

10,000 mile oil change interval using only Lubro-Moly Top Tec 4200LL & MANN filters.

Chain stretch can be checked with VCDS somehow on the later engines, but not our 2010 CATA.