Audi RS4 Avant B8.5 - Used Advice

[Daniel-89u1d]

Morning all, i'm venturing into the classifieds looking at used Audi RS4 Avant B8.5's and have a budget of around 27k - this seems to present motors of around 70-80k in mileage with a decent spec. Aside from the obvious good service history and oil change intervals what are the things i should be looking out for?

Am i right in thinking the RS4 engine does not have same timing chain / tensioner issues as the S4 version of the engine?

I'd be moving from a 2017 BMW 335d so would be dropping a lot of torque but feel the sound / top end power would be worth it - i hear these engines need a lot of work to get them singing but are they that lazy low down in the rev range?

A good read online only seems to mention the bad things (as always) so i'm hoping you guys can offer a general overview and if these engines / cars are more trouble than they're worth when the mileage gets up to 70/80k and more.

Thanks!

[Dr G]

They were expensive to maintain with 20k miles, and they're expensive to maintain with 80k too.

I shall not break rules and link to my own video but if you were to throw "audi rs4 avant b8 buying guide" into youtube the 2nd one (published 22.3.20) is me yammering on for 10 minutes about all the things that go wrong on them.

They're great cars, but an awful lot of owners don't want to spend the neccesary to keep them that way.

[Daniel-89u1d]

I actually watched your video last week, very informative, cheers for the reply.

[Dr G]

...and no, they don't suffer timing chain issues.

[DaveA8]

I’m no expert but I think the sports diffs on these and RS6 , A8/S8 (up to 2017) are essentially the same
Over 4 cars ( 2 x A8 and 2x S8) each has had a full sports diff replaced.
I sold one to my brother in law and that even after being replaced has gone again ( outside warranty), I thought it was 5 to 7k to do but I saw an email and they now want nearly 12k.
It’s not the seals but something inside that sends oil out a vent hole on top, each one of them started leaking oil. Even now turning sharp left or right I dread a light coming on
I say they are essentially the same as the housing appears very similar whether they develop the same fault I don’t know but make sure you have a good warranty

[ninjag]

I believe the S4 chain issues may have been pretty much sorted late facelift (2014/15 CREC engine). The part numbers for the tensions etc have modification codes which would certainly suggest this.

[DaveA8]

I’m no expert but I think the sports diffs on these and RS6 , A8/S8 (up to 2017) are essentially the same
Over 4 cars ( 2 x A8 and 2x S8) each has had a full sports diff replaced.
I sold one to my brother in law and that even after being replaced has gone again ( outside warranty), I thought it was 5 to 7k to do but I saw an email and they now want nearly 12k.
It’s not the seals but something inside that sends oil out a vent hole on top, each one of them started leaking oil. Even now turning sharp left or right I dread a light coming on
I say they are essentially the same as the housing appears very similar whether they develop the same fault I don’t know but make sure you have a good warranty

[ninjag]

DaveA8 said:

I’m no expert but I think the sports diffs on these and RS6 , A8/S8 (up to 2017) are essentially the same
Over 4 cars ( 2 x A8 and 2x S8) each has had a full sports diff replaced.
I sold one to my brother in law and that even after being replaced has gone again ( outside warranty), I thought it was 5 to 7k to do but I saw an email and they now want nearly 12k.
It’s not the seals but something inside that sends oil out a vent hole on top, each one of them started leaking oil. Even now turning sharp left or right I dread a light coming on
I say they are essentially the same as the housing appears very similar whether they develop the same fault I don’t know but make sure you have a good warranty

I had a quick look at some of these models and part numbers and this is what I found if it helps at all:

2015 A8/S8 and RS6/RS7 (basically A6 upwards): 0BF 500 043 R

Apparently this replaces 0BF 500 043 B but from what I can see this is the sports diff from the pre-facelift S4/S5. It's difficult to know if the modification code is from supersessions or due to different applications related to the rear axle code.



2015 RS4 and RS5 part number is: 0BF 500 044

There's no modification code. The last digit is usually the side when it's a sided part, so not applicable here. It seems to have been in the RS4 since 2013 so if it were a design improvement of the 043 R I would have expected to see it listed for the RS6 and S8. Maybe it's more to do with application?

[DaveA8]

ninjag said:

DaveA8 said:

I’m no expert but I think the sports diffs on these and RS6 , A8/S8 (up to 2017) are essentially the same
Over 4 cars ( 2 x A8 and 2x S8) each has had a full sports diff replaced.
I sold one to my brother in law and that even after being replaced has gone again ( outside warranty), I thought it was 5 to 7k to do but I saw an email and they now want nearly 12k.
It’s not the seals but something inside that sends oil out a vent hole on top, each one of them started leaking oil. Even now turning sharp left or right I dread a light coming on
I say they are essentially the same as the housing appears very similar whether they develop the same fault I don’t know but make sure you have a good warranty

I had a quick look at some of these models and part numbers and this is what I found if it helps at all:

2015 A8/S8 and RS6/RS7 (basically A6 upwards): 0BF 500 043 R

Apparently this replaces 0BF 500 043 B but from what I can see this is the sports diff from the pre-facelift S4/S5. It's difficult to know if the modification code is from supersessions or due to different applications related to the rear axle code.



2015 RS4 and RS5 part number is: 0BF 500 044

There's no modification code. The last digit is usually the side when it's a sided part, so not applicable here. It seems to have been in the RS4 since 2013 so if it were a design improvement of the 043 R I would have expected to see it listed for the RS6 and S8. Maybe it's more to do with application?

Thanks, as it happens Dr G made a good point about get the correct ref from Audi, I did that for him and he found a suitable part in Poland, I gave him a contact out there and a week later it was through customs, approx £450. Who knows with these things but at £1k inc fitting , I think he's very lucky

[bristolbaron]

One thing that’s not been mentioned yet, and the biggest obvious failing on the RS4 is DRC issues.

Leaks are common and almost certain by the mileage you’ve mentioned. You can work your way around the car replacing pipes and shocks as and when they go, but it’s a long (and expensive) process.

The B7 gang have accepted replacing the lot for coilovers or the CRS performance Koni shocks as the hassle free solution, but B8 owners tend to still be repairing. I went for CRS shocks and couldn’t be happier!

Look out for lumpy gear changes from 1st-2nd.

I’ve had mine since last August and it’s everything I’d hoped it would be. I’ve averaged 26mpg over that time too, so not the wallet ache you’d expect!

[Murph7355]

bristolbaron said:

....

The B7 gang have accepted replacing the lot for coilovers or the CRS performance Koni shocks as the hassle free solution, but B8 owners tend to still be repairing. I went for CRS shocks and couldn’t be happier!

...

Not so for everyone.

I'm in the B7 gang and won't move the car to coilovers. The DRC system is so good, and a serious part of what makes the RS4 special.

OP - try both a B7 and a B8. The B7 is the more engaging drive, and there's nothing in it performance wise. The 4.2 V8 needs revs to really fly, but the manual box in the B7 makes that easy. The B7 is obviously older, so the trinkets aren't as "modern", and there's less space (with the proper RS4 wingback seats, there's as much room in my 911 as in the RS4). But IMO it's very much worth a look - I contemplated getting a B8 when they were released to replace the B7. Didn't bother. Ditto the B9. Even less so.

[Dr G]

Agreed, I'm yet to drive an aftermarket setup on either I was completely sold on.

In terms of preserving value originality is certainly better too.