stickman1970

Hello Forum.

Well as of last week my 2012 A8L hit 200K miles.

I'm thinking I may sale and trade up to a newer model next year.

What is everyone's thoughts about the 4.0L versus the 4.2L engine?

mtnboydl

Nowhere near as reliable as the 4.2....200k miles would have you through at least one set of turbos....

DocTJ

omg man. more power to you!
whats the CEL about?

AudiMaster Tech

Awesome mileage! My cousin has a 2011 A8l 4.2 and I have a 2013 A8l 4.0t and the cars are very similar but the 4.0t performance is a lot better compared to the 4.2. That's about it though, 4.2 gets better mpg and reliability compared to the 4.0t. I'm glad I got the 4.0t over the 4.2 because its a lot faster and more fun but if you don't drive your A8 aggressively then it wont really matter to you but if you do then definitely get the 4.0t. Its a true sleeper and is fast for such a large car. Its an amazing engine with awesome performance and responds well to tunes.

stickman1970

Thanks for the info about the turbo reliability. What mile marker have you guys seen the turbos going out?

Regarding the CEL, not sure yet. It would go off come on, but couldn't catch it on to scan for it. Now I just haven't had time to scan it now that it's on all the time.

Taking it in later this month for English e and trans mount replacement.

stickman1970

Great info.

What milage is on your 4.0T?

Have had to replace your turbos?

AudiMaster Tech

Its a little weird, my co-worker who owns a tuning shop said he saw one go around 30k and one around 90k so its very unpredictable. My 2013 has 76k miles with original turbos and screen. I'm changing the screen this week and we are going to examine it and the condition of the turbos.

stickman1970

I've been looking at replacing my 4.2 with a 4.0T.

Should I be looking at on that has already had the turbos replace?

AudiMaster Tech

TBH not sure, it might be difficult to find one you like that already has a dealer record for that. Mine didn't have any turbo or oil screen records but it did have full dealer service history since day 1. I still bought it knowing it could have turbo failure but I'm changing the screen as preventive maintenance and will be looking at the turbo condition. Its not the end of the world if the turbos are bad, they aren't cheap but not super expensive and on the A8 its not that difficult to change them. When I was shopping I found it hard to find one with turbos and screen already serviced since dealer won't really do that until the failure actually happens. If your have the money you can buy one with a warranty which would probably be a facelift but if not then you might have to roll the dice with the turbos.

stickman1970

True.

Thanks for the insight.