My family loves the car and I still do although I don't like the squeaks on the front suspension when it's cold hence the 98%.
Hey, don't want this to come off the wrong way but this is not the car to go "cheap" on, not change the oil, or ignore your wifes advice of not doing preventive maintenance (listen to that woman, shes smart!). The A8 is a very complex machine and can be a nightmare if not taken care of. The approach "if aint broke why fix it" is playing russian roullette because WHEN something does break, it can be a domino effect for other issues that will hit you all at once and leave you with a hefty bill. This can be prevented of course with proper preventive maintenace.
Don't gamble with an engine on an 80k German luxury sedan by not changing the timing belt and playing the "how many miles can i go game". High risk game my friend, like believing some random chick you meet in the club who says "i'm clean and i'm on the pill!"
Realize what you bought, properly take care of the car and it will take care of you. If you are trying to make your A8 equal ownership costs of a Honda Accord, then you are in for disapointment and in the future will hate the car because it will turn into a money pit.
while I do my oil changes at or before the required miles (or had the dealer do them under AudiCare thru 75K), I burn no oil. Zero, and it doesn't even move down the dipstick any noticeable amount over the whole 10K run. Thus, it's simply the fill at the oil change and no more. Gets boring after a while checking it on occasionally at gas station w/ never a change. At 101K currently; 2006.
I need to check the timing belt to see if it can go 155k miles like my 96 A6 (and still running).
Just curious, how do you plan to "check" the timing belt? Pull the front cover and visually inspect? I ask because I'm at 80K myself and like you previously went to 100K on my '03 allroad before timing belt with no issue. Just been internally debating on "when" to change it on the D3.
It uses the rear brake parking motor to figure out cumulative wear. But if someone reset the warning with a false pad value after they were already worn some, I don't think the system can catch this. It just does a subtract from the reference value it is given for starting pad thickness AFAIK. Someone may have mistaken the simple open rear pads choice for other servicing, vs. the open and replace setting for installing new pads.
Twirl the six shooter and pull the trigger...rationalizing.
It's all a calculated risk. Inspect the (reinforced) belt until the proverbial cows come home, but then if one of the pulleys fail or the water pump freezes it can be over in weeks, days, hours or a fraction of a second. Any of those scenarios that can rip or skip the belt, reinforcement and all, and boom!
If you change it every 30K miles (what was the C5 RS6 interval for the 4.2T in 2003, the shortest ever on an Audi), your chances of screwing something else up may be as high or higher than the belt taking a sudden powder. 75K for the common normally aspirated 4.2's is what Audi moved it down to from its old higher recommendation (105K IIRC). They literally did it retroactively via a TSB even to prior year models, so figure something was catching their attention in the repair tracking. But, it could have been over in Honda world that things caught Audi's technical OR legal attention, where ultimately Honda wrote checks in probably the 10's of millions after a bunch of egg on face timing belt blow ups in interference engine Preludes and others.
If you put these together, you can surmise the rational lower risk range even in Audi think was probably in that 75 to 105K zone where the maintenance spec was on the non turbo belt driven 4.2 was at various times over its run. Of course if you do just the belt narrowly, that's just the low probability scenario the belt somehow just spontaneously self destructs or wears itself into oblivion or stretches (in spite of its reinforcement). It still does't deal with the water pump, idler pulleys and tensioner unless you change them out too.
Or you can go to whatever miles. Chances are it will ultimately be a water pump failure or thermostat failure that forces the issue, and perhaps 8 or 9 out of ten either one will come on with enough warning you can catch it. Maybe one in ten though that you never feel the head shot striking fast, having spun the proverbial revolver one too many times. There is a time for that too though, like when you reach the last "who cares" just drive it into the ground stage where the interior is shot, motor smoking, tranny failing, etc. Those "not worth it anymore" scenarios tend to come pretty late in life for Audis compared to many other "beater" cars though. And by those miles, you'll just call the last rites truck with the hook and kiss it goodbye when the time comes, belt failure or otherwise. ... Pay me now or pay me later is another less graphic apt saying.