Does temperature effect the performance or clunkiness of the DRC ?.....

[4.2Crew]

Just purchased the car a week ago....

Prior to test driving the car, it had been sitting in a 65F heated garage and put on a lift so I could inspect the underbody etc. I specifically examined each strut for obvious leakage (nothing.) While on the 1/2hr test drive, the outside temp was 35F. No obvious clunking or rattling. On the 800 mile drive home, the temps dropped from mid 30's to as low as -20F... Suspension clunking and rattling then became apparent, and seemed to get worse and worse...

So, is it possible the colder temps or temperature gradient within the DRC system (warmer fluid in/near strut, very cold fluid near the actuators) caused the seals to just now start leaking?... Or, could it be slight volumetric shrinkage of the hydraulic fluid---resulting in a drop in DRC pressure?... I know hydrualic fluid is theoretically incompressible under load, but is it volumetrically stable with respect to temperature?

Does anyone notice suspension (DRC) rattles that are temperature dependant?...

Will replace the suspension either way in the next few weeks... Just was curious what other's have or have not noticed.

[MaxRS6]

I don't have an answer to your ?. However; that garage is awesomeness! Just need a lift and higher ceiling to make it full awesomeness. Heck- you probably have the lift hidden in the floor. :)

However; you have my garage beat by infinity...;0

[4.2Crew]

I don't have an answer to your ?. However; that garage is awesomeness! Just need a lift and higher ceiling to make it full awesomeness. Heck- you probably have the lift hidden in the floor. :)
However; you have my garage beat by infinity...;0

Thanks, Max!

Oh No!... Don't get him started!

First two pics are from about 7 years ago after resurfacing the floor and installing the lift... I know, pics are too small. We no longer have the A4-----Sold it after I replaced the turbo for the second time due to wastegate failures.... Vowed to never own another car with hairdryers! Oops. The lift is a 48" Snap-On scissor lift made by Ammco. Picked it up used on Craigslist. Told the wife: "If I can get a lift, I'll do one timing belt and it'll pay for itself!" Can't image garage life without it...

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http://www.rs6.com/images/misc/pencil.png
http://www.rs6.com/images/misc/pencil.png

[MaxRS6]

That is too funny as I did not know abut the lift. That is full awesomness and I am..


http://images.quickblogcast.com/72745-63839/greenwithenvy.jpg?a=70
green with envy. Great setup you have there and well done!

[ben916]

well, your climate is not nearly the same as mine, however...

I notice more clunking in the mornings more than evening.
What is peculiar is that on surfaces that might have a minor bump or transition or seam and it will be "noise-fest".
But on rather bumpy surfaces, the noise is different.

[4.2Crew]

well, your climate is not nearly the same as mine, however...

I notice more clunking in the mornings more than evening.
What is peculiar is that on surfaces that might have a minor bump or transition or seam and it will be "noise-fest".
But on rather bumpy surfaces, the noise is different.

Funny you mention that, Ben... I brace for the larger bumps expecting the worse---nothing! But, small, close together minor bumps sounds like there are old tool boxes half-filled with bits over each wheel and in the trunk!....

[4everRS]

4.2, that is likely a control arm issue. I bet your bushings are worn out.

I don't notice a difference in the temps. I suppose there could be issues if air entered the system somehow.

[4.2Crew]

4.2, that is likely a control arm issue. I bet your bushings are worn out.



I thought the same thing... So, I put the car on the lift and shook the wheels, the uppers seem fine. On the A6, when an upper control arm went, I could very easily tell which one was bad. Maybe a lower control arm is at issue? Any way to check without just replacing?

[4everRS]

Yep, just get it on that fancy lift, grab the the lower rear and twist it back and forth. If it moves more than a couple degrees, they're shot.

[4everRS]

Btw, I know where my next tbelt job will be done! :)

[MaxRS6]

^Now that just ain't (Arkie) fair. I have no local peeps with mad hatter skillz..Poor Max...;(

[4.2Crew]

Btw, I know where my next tbelt job will be done! :)
Anytime!... Friends and neighbors use it all the time! Yes, some people still do their own work!

[hahnmgh63]

Sometimes the rubber bushings just get tears in them that can't be felt by the standard attempts of moving the wheel assembly but when the get two tons of weight on them they can clunk fairly well. If you have over 60K on the RS6 they probably need to be changed. I found the upper rear to be the worst for tears but the uppers are the easiest to change but they are all fairly easy to swap out.

[NSU RS6]

That is too funny as I did not know abut the lift. That is full awesomness and I am..


http://images.quickblogcast.com/72745-63839/greenwithenvy.jpg?a=70
green with envy. Great setup you have there and well done!

Wow.

My wife would give me all kinds of lifts if my garrage was that spiffy.

That is really nice, and I am inspired. Been thinking 12' dual posts, because I am done going under cars on stands and a scooter. At least until next week.......knockknock.

I presume you built that garage and had the floor/engineered altered as shown?

I like the scissor jack lifts. They are inexpensive, and work for most issues you need a lift for. Engine pull - perhaps not. But to be able to do so many other things for all of the other cars.....WIN. My biggest issue with them is that they are above floor. You have solved that.

Nicely done.

[lswing]

Funny you mention that, Ben... I brace for the larger bumps expecting the worse---nothing! But, small, close together minor bumps sounds like there are old tool boxes half-filled with bits over each wheel and in the trunk!....

This is exactly how my DRC rides, and it does seem harsher with colder weather, probably due to all plastic parts of the car being firmer. Bigger bumps get soaked up pretty good, but there are a few spots around town that have lots of little bumps in a row, if I had fillings that were ready to fall out this would do it. I get the impression the DRC has too much pressure to compensate for the car being so heavy, and can't adequately compress on little bumps...All I can say is kw-v3...one day! I will double check the bushings though...

[mik15]

i have been feeling this lately here as well, the temperature isn't that low, but we do get in the morning like 55F or lower, and i can hear a small difference, at least until i drive a few miles and then it's ok after the suspension warms up, but yeah, on the small bumps it's the problem, if i hit pothole, though it's hard to do it here, no problems at all, it soaks it up very good...since i have just overhauled the DRC i will wait until it fails again before switching to an H&R or maybe a KW...

BTW - great garage you have over there!!!

[kilian tuning]

ive got that when the engine is cold, and vibration too...all gone when engine is warm...

[4.2Crew]

Wow.

My wife would give me all kinds of lifts if my garrage was that spiffy.

That is really nice, and I am inspired. Been thinking 12' dual posts, because I am done going under cars on stands and a scooter. At least until next week.......knockknock.

I presume you built that garage and had the floor/engineered altered as shown?

I like the scissor jack lifts. They are inexpensive, and work for most issues you need a lift for. Engine pull - perhaps not. But to be able to do so many other things for all of the other cars.....WIN. My biggest issue with them is that they are above floor. You have solved that.

Nicely done.

Thanks!
We moved into the house in 2005. It was constructed in 1978. Garage floor was severely cracked and sinking in areas... We had to do something due to snow melting off the cars, seeping thru the cracks and causing more errosion under the slab. We opted to simply mud jack to relevel and stabilize the floor. Then, I cut the floor for the lift using a rented cement diamond saw, excavated the concrete and about 18" of fill. Repoured high-strength concrete to a level for a flush install. We then hired an epoxy floor contractor to "tie" and grind the floor level before coating.

Tear-out, repour garage cost (no lift, no epoxy): $8000 (Lots of hand work due to paver driveway)
Mudjacking, concrete saw and mixer rental, epoxy contractor, lift, diamond plate cover: $4100

Car can be 48" in the air in 2 minutes.... Priceless!

[ben916]

ah, my job is done here.... audible paranoia spread...

[Hy Octane]

My DRC is stiff and perfect when its cold in the mornings but as I drive for awhile and the car heats up, the ride gets softer and less stiff. I attribute this to an improperly filled DRC.. They didnt do it in a room where the ambient temp was 65F or less. It was done in SoCal on a hot day with no AC in the facility.. So, the oil they use for the DRC was not as cold as it should have been.. this results in a thicker fluid when cold but it thins out when warm softening the ride..
Since we know that nobody designs a car to have a suspension that changes its firmness as the temps rise and it didnt do this when new, its must be close to what I think is the answer.