2008 S6 Purchase - Yes or No? Advice?

A6 All/ S6 All
#1

Hello.

New member here. I currently own a 2008 Audi S4 Cabrio but I am seriously looking into purchasing a 2008 S6 with 70K miles on it. I test drove the car a few days ago and REALLY liked it. The V10 power is awesome and the luxury features of the car are really nice.

The car does have a few issues I noticed. Common oil leaks, headlamp adaptive headlights warning, and the sunroof seems to need its motors re-calibrated. The dealership is changing several of the gaskets on the engine to fix the oil leaks. They were able to repair on of the head lights as it was the common broken wire; the other lamp is being replaced. I am not too concerned about the sunroof as I have seen there is a TSB that has a procedure that may fix its issues and even if not, its not a big deal as I never use sunroofs.

I am aware that the engine will need a carbon clean and probably a new intake manifold.

Any other problems that I should be aware of? Any advice or recommendations? I work on my own vehicles and can pretty much do most work that would be required.

Thanks.

#2

The V10 is definitely the difference maker in the Audi S6 C6 over other vehicles - that’s why most of us are here! But depending on your budget, I’d prefer to get a S6 C6.5 ('09-'11) or really '10-'11 since it’s post facelift, upgraded MMI and some parts updated from C6 (excluding the IM). I just have superstitions at this point from the 2008s after seeing/hearing some of the stories behind them.

Your biggest threat to look out for is no doubt carbon deposits. You can combat this by:

  • Performing carbon cleans every ~25K miles
  • Drive it like you stole it (the car prefers to be in motion as opposed to idling, especially when warming up. It’s recommended as soon as you start it, drive it.)
  • Install JHM intake spacers and SAI delete to keep carbon deposits to a minimum
  • Use fuel additives (I prefer Liqui Moly since it’s German, but Lucas works just as well)

JHM also offers plenty of performance parts like a great tune, exhaust setup and lightweight parts to crank up the performance… if you weren’t satisfied with the 435HP already. It’s also rumored that JHM will be releasing a supercharger and possibly custom headers as well.

I’ve owned mine for less than a year, but it’s been pretty reliable. Only control arms and a CV axle bearing needed to be replaced/rebuilt.

My advice is to get the car inspected by a third party service or your personal mechanic if the car is in your area - don’t trust the dealership. It’s also a GREAT idea to check the vehicle’s Carfax for maintenance, so you know what you’re getting into BEFORE purchasing the car. That way you can budget accordingly and prepare sooner than later.

We also have a Audi S6 C6 maintenance thread somewhere around here that can help you know when to check/replace certain items. :slight_smile:

EDIT:

I found the service maintenance thread. Click here.

#3

We should sticky the above, great advice.

In regards to buying one I don’t think anything else competes even south of 30k. Even over that I would question what you would replace it with. Does everything so well and has character to boot in most peoples opinion at least.

#4

I have had good luck with mine. Only minor repairs, brakes, and tires in the 33,00 miles I have put on it in the 18 months of ownership. Did a 2300 mile road trip around spring break. There is nothing quite like hustling a C6S6 down the freeway at 90-100 for hours at a time. I have had over 40 different cars, and this one is my favorite so far!

#5

I’ve owned my '08 S6 for 4 years exactly. Put 53k miles on it, and it presently has ~115k miles. Had some struggles with what turned out to be injectors and a couple of other minor things. Like GRS6 say, a '10 or '11 might be nice, but I wouldn’t let that stop you. Maintenance is key though…

#6

Having a 4.2 S4 would probably mean you already know about JHM as they OWM the 4.2 market and have done the same again with the 5.2.

I would start by posting up the car fax or ask the dealership on the owner history or service history. That will really add to the list of things mentioned above.

What you want to look for is the link GRS6 posted is a great link if I do say so myself but seriously
http://audirevolution.net/forum/index.php?topic=4103.0 follow that. Everything GRS6 said is spot on The only thing I would really add is that you need to get your injectors serviced. That is a big must.

I would have the dealer do a compression test and post those results. The injectors are common to flow down from the target range by quite a bit. If they fall down too far you can see damaged cylinders and that will show up in a compression test. JHM does a high pressure test and service its worth the money and something to add to the must list.

#7

Thank you everyone for the excellent advice.

I am going to get the car. I do have the CarFax for the vehicle and it does show that it had regular maintenance. I doubt it has ever been carbon cleaned so once I have the car in my possession, I will be doing a carbon clean myself. I will also get the JHM intake spacers and replace the injectors just in case.

Will also do an oil change and maybe trans fluid and differential fluid change as well.

#8

Also, I HIGHLY recommend buying flowmatched injectors from JHM; even with the core charge, they’re priced about the same as new, and from experience (I’ve bought about 15 injectors now total, a mix of used and new) it’s almost a waste of time to even buy new. There’s something like a +/-15% variance in flow rate even among brand new. Careful when you pull the injectors off; the locking tabs are very fragile after they’ve been on the engine a while and break very very easily making them useless if they do. You’ll see what I’m talking about when you break one :wink:

Do coils & plugs while you’re there as well.

Trans flush; I did new fluid and filter on mine with a kit from ECS; It made a difference. Not huge, but it got rid of that awesome “ZF lurch”.

DEFINATELY get your exhaust modded. The difference in sound goes from “this is cool” to “OMFG I have to rev this thing everytime I go under a bridge, pull into the garage and live life from one parking structure to the next!” I bought the JHM exhaust; it’s fairly spendy, but there’s no drone and really doesn’t make much more sound than stock unless you’re using the loud pedal. The fit&finish is on par for the price point. Cheap alternative would be to have a muffle shop cut out the resonators and mufflers and replace with flowmasters - the sound is similar, outside, but apparently there’s some drone sometimes inside. YMMV

I looked for a link to the 2017 MMI Navi update I bought off ebay for like $12, but the seller is gone :frowning: Not sure what the dealer charges, but it’s not cheap.

I’d also look into a control arm kit & maybe new struts. The kits are reasonable at around $400ish for the set and it’s a remarkably dramatic difference on a 10 year old car.

#9

So here is my list of things to address on the S6 once I get it:

  1. Change Oil and Filter
  2. Replace windsheild - has a crack in the current one. (Won’t cost me anything as its covered under my insurance and Kentucky has no deductible which is nice).
  3. Carbon Clean and JHM Intake spacers (will probably change out injectors at the same time).
  4. Trans fluid and filter
  5. Diff fluid
  6. Replace filters with K&N’s

My main goals with the car are to keep it stock and just enjoy driving it. I just want to make sure that is runs well and lasts a long time. I am really looking forward to enjoying the power and luxury of the car.

I will probably get the Bentley Manuals for it and Vag-Com also.

#10

^^This is well worth the money. I use these a lot.

#11

Good starting list! Have fun, you’ll love this little beast of an all-arounder.