I have a 3.0tdi A8 D4 2014 with 113k. I have tried to find information online regarding the timing chain. There is a lot but I can’t find anything definitive.

Do I just need to service and replace the guides and tensioner or is it best to do the chain when you are in there.

What mileage should I be looking at, is this about right or should it have been done earlier or leave it till later.

Thanks 🙂

 

 

I would fit a new chain while I had access, to avoid doing the job a second time at a later date. Chains stretch over time until eventually they are longer than the tensioners can accomodate.

My A8L 2014 has 155k miles on it now. Still original chain I think. Unless you are noticing an issue dont stress about it. If you have the money to blow on getting a new chain, make sure the mechanic buys a full kit with new gaskets, tensioners, chain etc. 

IMG_7685.heic

It's a big job on an A8 including engine removal 

I am looking at an A8 D4 3.0TDi with 70k on - I went to Audi last week and they said that the timing chains (which are at the back of the engine) are a lifetime fit - so no maintenance necessary. Ribbed belt is 140k miles.

As said if at back of engine thats expensive if needed at all

I know this is a little late, but please ignore the claptrap about chains being a lifetime fit. They aren't. Like everything in life they wear out. Have a look at the VAG Technic Youtube channel and ye shall be enlightened.

On 1/27/2026 at 2:58 PM, micdev42 said:

I know this is a little late, but please ignore the claptrap about chains being a lifetime fit. They aren't. Like everything in life they wear out. Have a look at the VAG Technic Youtube channel and ye shall be enlightened.

I second this good advice. 

On 1/27/2026 at 2:58 PM, micdev42 said:

I know this is a little late, but please ignore the claptrap about chains being a lifetime fit. They aren't. Like everything in life they wear out. Have a look at the VAG Technic Youtube channel and ye shall be enlightened.

I got it done cost including a load of replacement plastics from the V bank was in excess of £6k. Painful but overall worth it as I now have 120k more miles to do 😀

3 hours ago, Jamsey1969 said:

I got it done cost including a load of replacement plastics from the V bank was in excess of £6k. Painful but overall worth it as I now have 120k more miles to do 😀

Glad you got sorted 

Hi, changing a high milage TC before it's absolutely necessary depends on whether your an owner or a buyer. If you're an owner, wait until it either comes up during a service, MOT or you hear the tell tale signs on startup. If you're a buyer, if the car has done over 70k+ and it's not mentioned in the servicing, it's more of an issue.

Chains rarely just suddenly break, they tend to stretch leading to a metallic knocking on a cold start as the tensioners pick up the slack in the suddenly moving chain. If you're a potential buyer and hear this "knocking", walk away, if your an owner and have a 80/90k+ car on it's original chain, cross your fingers, I see a bad moon is rising. 

There are several good YouTube videos on the TC subject.     

Apologies for contra opinion Basil, but there should never be any element of ‘cross your fingers’ with this. Serious chance of fingers getting burnt here.

1 hour ago, AudiA8W12 said:

Chains rarely just suddenly break, they tend to stretch leading to a metallic knocking on a cold start as the tensioners pick up the slack in the suddenly moving chain.

Agreed, which means one gets plenty of audible warning when it is time to change the chain and tensioner, so no need to reject a car that has covered x thousand miles simply because it has not had a new chain. Just factor the cost into your servicing calculations based on whatever story you choose to believe about service life.

1) Re the moderator comments, yes I totally agree, my "cross your fingers," comment was my attempt at levity, naturally any issues should be investigated and addressed with necessary urgency.

2) Re Clifford's comments, it does depend on ones outlook. For me likely TC replacement would be a major factor impacting any potential purchase. If the seller was willing to compensate me for potential risk then I would be amenable to price negotiation, however that's me, others may be willing to absorbing the full risk and cost of any future work.   

To be clear, for me, an Audi car with 90k+ miles, with its original TC is a risk, just for context, my personal experience relates to a w12 on 150k miles, with no TC maintenance. I really wanted the car but the seller would not negotiate. I walked.