DRC Recall in US/Canada

[Sims]

... so eventually the shock absorbers on every car will need replacement - even on a 1 €1m+ Bugatti Veyron.

You seem to know a fair bit about Veyrons,sounds like you have access to one.

[PetrolDave]

... so eventually the shock absorbers on every car will need replacement - even on a 1 €1m+ Bugatti Veyron.

You seem to know a fair bit about Veyrons,sounds like you have access to one.

It's top on my (wife approved) wish list when I win the lottery

A Veyron is just another car so it will suffer the same failures as all other cars. I could have said Rolls Royce Phantom, Pagani Zonda,Koenigsegg, etc...

[Steve_C]

The shocks take large sudden loads every time you drive over a pothole (very common on UK roads), a raised bridge expansion gap (there's some horrible ones of those on the M27), or similar raised or sunken "feature" on the road.

Well, I'm either lucky or the roads near me are in good nick. Although I do make a point of avoiding pot holes etc. since I hit one, years ago, on a driving lesson and got a puncture!

[aidanjaye]

Had 80000 miles on my S4 and still on original shocks, had 65000 miles on my GTR on original shocks - no noticable leakage or slack.......
......maybe the RS4 would have been better wit high quality shocks (no drc) as standard.

[Sims]

Had 80000 miles on my S4 and still on original shocks, had 65000 miles on my GTR on original shocks - no noticable leakage or slack.......
......maybe the RS4 would have been better wit high quality shocks (no drc) as standard.

Agree with you about the long life on normal shocks, even on high performance cars.

The RS5 has the option (not for UK AFAIK) of the sports suspension which is not DRC and is faster at tracks.

However, I do like the comfort of the DRC.

[PetrolDave]

However, I do like the comfort of the DRC.

+1

Near home there's a stretch of road that has lateral ridges like an old fashioned washboard.

In both my previous B6 S4 it was almost painful to drive over (and it wasn't much better in an A4 1.9TDi Sport I had briefly), but in the RS4 DRC makes the straight line ride quality much softer and more compliant, yet you still get much better cornering than the S4 as well.

A much better ride/handling compromise than the S4 or A4 Sport I reckon...

[ArthurPE]

the pressure is actually 16 bar to 12 bar (235 to 176 psi) afaik
I'm sure there is a natural variation with air/fuid temp too...

and it's the springs that carry the load, the dampers dampen the spring oscillation...

does anyone know the spec?
I know 12 bar is the NO GO low limit
I thought they were initially charged to 14 bar...but I've heard 16 too

PSi or BAR, it would make very little difference to calculations.

spoken like a true non-engineer
numbers/magnitude are kind of the ONLY thing that matters when it come to calculations???!!!

[ArthurPE]

I agree

one impulse can destry a shock, or shorten it's life/efficiency
just like it can bend a rim...

but most folks aren't in tune enough with their car (one reason for the percieved higher rate with issues with RS4's, M3's, etc.)they will never notice it...

imo one issue with the DRC...you hit a big impulse with a gas shock, gas is compressible, it can take more abuse...hydraulic fluid is not, so it has to go somewhere, and it's thru the seals...the accumulator can only absorb so much...now is a little leaking over a long time a big problem? imO no, charging is a viable option...

Having never had to replace shocks on a car I'm wondering what is the reason for the wear and tear?

Wow, I'm surprised.

Until I could afford to buy new cars I'm pretty certain I had to replace at least one pair of the shocks on every second hand car I've owned. The RS4 is the first new car that I've owned for more than 3 years, so having to have replacement shocks comes as no surprise to me.

And that was in the days before speed bumps, so they're not the only factor but they are an important one. The shocks take large sudden loads every time you drive over a pothole (very common on UK roads), a raised bridge expansion gap (there's some horrible ones of those on the M27), or similar raised or sunken "feature" on the road. No mechanical system that is affordable can take those loads for ever, so eventually the shock absorbers on every car will need replacement - even on a 1 €1m+ Bugatti Veyron.

[Sims]

the pressure is actually 16 bar to 12 bar (235 to 176 psi) afaik
I'm sure there is a natural variation with air/fuid temp too...

and it's the springs that carry the load, the dampers dampen the spring oscillation...

does anyone know the spec?
I know 12 bar is the NO GO low limit
I thought they were initially charged to 14 bar...but I've heard 16 too

PSi or BAR, it would make very little difference to calculations.

spoken like a true non-engineer
numbers/magnitude are kind of the ONLY thing that matters when it come to calculations???!!!

And as an Engineer do please explain to ^Qwerty^ and the rest of us.

& do remind me how many RS4's built, and how many have had DRC issues.

[Sims]

I agree

one impulse can destry a shock, or shorten it's life/efficiency
just like it can bend a rim...

but most folks aren't in tune enough with their car (one reason for the percieved higher rate with issues with RS4's, M3's, etc.)they will never notice it...

imo one issue with the DRC...you hit a big impulse with a gas shock, gas is compressible, it can take more abuse...hydraulic fluid is not, so it has to go somewhere, and it's thru the seals...the accumulator can only absorb so much...now is a little leaking over a long time a big problem? imO no, charging is a viable option...

Are you are suggesting M3's suffer the failure rate as RS4's.

Or that the Engineers were unaware that there would be big impulses or that hydraulic fluid needed to go somewhere.

The leaking over time is a problem, that's crystal clear.

Why haven't Audi adopted your suggestion of charging? Do they know something else?

[aidanjaye]

However, I do like the comfort of the DRC.

+1

Near home there's a stretch of road that has lateral ridges like an old fashioned washboard.

In both my previous B6 S4 it was almost painful to drive over (and it wasn't much better in an A4 1.9TDi Sport I had briefly), but in the RS4 DRC makes the straight line ride quality much softer and more compliant, yet you still get much better cornering than the S4 as well.

A much better ride/handling compromise than the S4 or A4 Sport I reckon...

It should be better than an S4 or A4 when you take it account the additional cost and time spent by Audi developing DRC.

[lengster1]

I dont find a little leaking ok at all,nor knocking for a year

[ArthurPE]

yes...a couple hundred M3 engines blew up and they offered a 100k (no time) warranty in the States...many more failed (not catastrophic thru the block) or lost performance prematurely

the diffs were/are fragile, mine, and many others were replaced
they all click/clack and rattle

there were actually legally mandated 'safety recalls' (not service actions)on the car (NONE on the RS4)

the shocks ae shot by 50k, most likely sooner

the leaking over time is not a problem, per Audi's TSB
and the fact that <1% have failed...

Are you are suggesting M3's suffer the failure rate as RS4's.

Or that the Engineers were unaware that there would be big impulses or that hydraulic fluid needed to go somewhere.

The leaking over time is a problem, that's crystal clear.

Why haven't Audi adopted your suggestion of charging? Do they know something else?

[ArthurPE]

it would be like explaining how to breath...
and my time is valuable...
as opposed to yours judging from your posting rate and the resulting insults/gibberish

30,000, give or take, world wide...
the numbers you quoted were from 2007
<1%, considerable less

And as an Engineer do please explain to ^Qwerty^ and the rest of us.

& do remind me how many RS4's built, and how many have had DRC issues.

[Sims]

yes...a couple hundred M3 engines blew up and they offered a 100k (no time) warranty in the States...many more failed (not catastrophic thru the block) or lost performance prematurely

the diffs were/are fragile, mine, and many others were replaced
they all click/clack and rattle

there were actually legally mandated 'safety recalls' (not service actions)on the car (NONE on the RS4)

the shocks ae shot by 50k, most likely sooner

the leaking over time is not a problem, per Audi's TSB
and the fact that <1% have failed...

We were talking about suspension/dampers, and you have moved on to engines, diffs & BMW safety recalls. Why are you so anti BMW? is it because they did not agree with Arthur? BTW how many BMW's were affected -less than RS4's. I know you like numbers

BMW shocks last 50k miles (or less but you don't know), that's more than nearly all the failures on the RS4 that you do know about.

And why have you not answered all the questions?

Would you be happy with a leaking suspension? We all know how particular you are.