03 S8 steering problem
 

Hi there,

Let me apologize in advance for the lack of the right terminology, please bear with me.
As I said before I bought the car a little less than 2 weeks ago, haven't been able to use it much at all for work related stuff.
I noticed a vibration when going over 70mph coming from the right side of the car (I dare to say front right side). I knew before buying it that right front cv boot had tear in it but the joint itself wasfine. Besides the tires were unbalanced and I had to replace them as well (less than 50% tread left).
I replaced the tires last Saturday and they were balanced. I asked the guy at the shop what could be the reason of the vibration and he gave me 3 possible reasons:
- problem with the tire itself
- problem with tire balancing
- suspension issue
After all this I still notice the vibration.
What do you guys think? Is there any relation between suspension and cv boot?

Thanks,
Leo

I don't think your CV joint will have much if any effect on your high speed vibration.
However, get your torn boot fixed as it can only result in joint contamination and wear.
It will need to be cleaned and repacked at least, or replace the joint altogether.

If your wheels have been balanced well, the suspicion shifts to the front suspension.
The front suspension on all Audi's of this era wear and are a maintenance item.
You have 4 independant control arms with 4 independant (small) ball joints and a steering tie rod end.
It's called Audi's 'Quadlink' front suspension, and you will only get 60-100,000 miles out of the control arms.
Now you can get inner bush kits, but they're pretty pointless, as the outer ball joints are the usual culprit.

Testing:
Jack up each side at the front (from the jacking points) and get the front wheel off the ground.
Grab the wheel at 9 and 3 and try to rattle left to right.
Grab the wheel at 12 and 6 and try to rattle up and down
Any movement indicates wear, and you can then try to see which joints are moving.

If it's just a tie rod, they're easy and cheap(ish) to replace - I recommend doing both sides.
Control arms are a bit more expensive and difficult.

Now there's two schools of thought on replacing arms:
One is to replace the individual arms as required.
The other is to buy a kit and replace all the arms, tie rods and sway bar links in one hit.
Then there's also the choice of OEM replacement or aftermarket brands.
There's arguements both ways, but ultimately it comes down to budget and what your confident with.

Wow, thanks for the very detailed explanation.
I'm planning on going from Orlando, Fl to Atlanta, GA in two weeks. Based on what you said, do you think is risky to make the trip before fixing it?

Thanks,
Leo

Depends how bad the movement/vibration issue is.
It'll be a judgement call.
If there's more than a few mm of movement in any given ball joint, I'd look to replace it ASAP.
You'd also have a tyre wear issue.

How good are you with the wrenches?
I replaced the entire front suspension (sans shocks) on my A4 in around 5-6 hours go to whoa.

Haven't touched the S8's yet, but it doesn't look any harder.
Just be careful around the headlight leveler if you have one (attaches to the front left upper control arm) - it doesn't look all that tough.

Otherwise an indy shop (avoid regular mechs with an Audi front end, they'll scratch their heads) can do it for probably 4-5 hours labour (less for individual arms).

I can't do this myself, never touched a car before, hehe.
I checked the service records and I found the following:
Date: 5/18/2011
Odometer: 87518
Parts:
- Rear brake caliper
- Rear brake rotors
- Rear brake rotors
- Front upper control arms
- Front lower control arms
- Front axles
- Suspension parts
- Castrol LMA brake fluid
Labor:
- Caliper - remove & replace - [includes: bleed system and replace pads if necessary] - rear, both
* (Combination) disc rotor - replace - each, rear
* (Combination) dis rotor - replace - each, rear
* Control arm - remove & replace - [Does not include alignment] - Lower, both sides, all
* Control arm - remove & replace - [Does not include alignment] - upper, both sides, all
* Axle shaft assembly - removal & installation - both
* Four wheel alignment - adjustment - [Does not include straightening or replacing parts]

Based on what you said before, the control arms shouldn't be the problem, right?
Since I still don't know a good indy shop around my area, I guess I'll have to take it to an Audi dealership.
I've been told that replacing the CV boot should cost around $300 with labor (maybe a little less). Can you tell me what I should expect to pay if the tie rod needs to be replaced? Am I missing something else here?

Thanks for the help,
Leo

This may have nothing to do with your vibration, but one item that made my eyes pop was the replacement of both axle shafts at 87k miles!!!!????

Were they actually REPLACED?!

Why? ...and more importantly: With what!? The previous owner was taken for a ride. I can't imagine any possible scenario that could have called for that expensive mistake. Does the paperwork say what brand (or supplier) of axles? Was this at a dealership?

Wow!

It seems they were replaced. There's no part number, it just says NPN. Most of the items say NPN, only suspension has something different, 4DO-412-395-B. I take it that's the part number.
The bill is around $3.7k, but the things related to front axles including labor is less than $500.
It seems to be an Indy shop from PA, not a dealership. The second owner had it serviced there since 2007 until I got it a month ago or so.
Although looking at the records it is possible the owner thought the same way as you, since that was the last major job done there and he did the timing belt job done at a different place :)
I guess we'll never know...

CV's are normally not a my first choice as the culprit for a high speed vibration problem...BUT with the info you have, I see a HUGE red flag here.

A giant and all to common "mistake" made by DIY owners and lazy/dishonest mechanics is dealing with simple ripped outer CV boots ($20 part, including grease, clamps, etc..), by tossing perfectly good, best quality made OEM axle shafts (worth about $600 each) and replacing them with cheap low-quality guaranteed-to-fail aftermarket axle shafts at about $80 each, before the mechanic jacks up the price.

These cheapest of aftermarket shafts, after just a few thousand miles (OEM shafts can easily go 1/4 million miles), quite often develop all kinds of problems with the inferior outer CV joints and the inner triple roller joints. Generally the symptoms of an outer CV gone bad is felt (and heard) at low speeds in corners...rhythmic clicking often felt through the steering wheel. Inner triple roller joints are tougher to trouble shoot...they can cause unexplained vibrations at speed, grinding or vibration under hard load or on hard decel...VERY unpredictable what symptom will appear when they've loosened up, have a bad internal bearing or even a roller broken off inside the boot.

I would find a way to take a close look at those axle shafts or have someone you trust with basic mechanic skills take a look. If you want to, at least try to find a brand name stamped on the inner and/or outer joint like "EMPI" (as bad as it gets).

At the price you stated, ALL my attention would be on those axle shafts.

What you describe about a bad CV happens to me. Even what you say about the steering wheel, it's like I felt something was wrong with it but I couldn't tell for sure because I never drove it before.
So I definitely need to change the CV boot as soon as possible and I'll ask a BMW mechanic I trust to check the axle shafts. Hopefully you are wrong, but it doesn't look it's the case, hehe.
Do you recommend doing both things at the same time? And how much do you think it will cost at a dealership? A little over $1k?

Thanks!

Repairing the ripped CV boot will not cure ANY problem...only prevent a future one, IF the CV is still OK.

If you already have ANY symptom I described, it's too late to bother with the boot.

Before you do any repair or buy anything, start by having your mechanic friend look to see what axles are in there and if he feels any obvious slop...Tell him to find a brand name marking...this will speak volumes as to the next step.

DON'T GO TO A DEALERSHIP FOR ANY REPAIR, unless there is NO other possible choice!!!! If the axles need to be replaced (if you find EMPI on the joints or obviuos "slop"), most members here swear by Raxles brand aftermarket axles...higher priced than the inferior Auto Parts store brands, but well worth the extra cost. If you don't have original OEM axles now (not the shaft part, the joints themselves) there is no need to spend the big bucks for OEM...Raxles will cost half the price and any decent Euro mechanic shop (or DIYer...I've always done my own) can install them.

AGAIN, before you do or assume anything else...have someone look at them (you could do this yourself, unless you're in a wheelchair) to at least see a brand name stamp on the joints.