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tunerb5
03-19-2007, 07:46 AM
My front uppers are shit again. I've aleady replaced them about 2 years ago. I maybe have 30-40 k miles on them and they are already shot. The car is slammed and I guess it shows. [headbang] . Guess next week I'll be replacing all the uppers, the tie rods, my blown bilstein shocks (also around 40k on them) and all new strut/shock mount since those are shot too. Thsi shit never seems to end.

ShawFM
03-19-2007, 08:00 AM
My front uppers are shit again. I've aleady replaced them about 2 years ago. I maybe have 30-40 k miles on them and they are already shot. The car is slammed and I guess it shows. [headbang] . Guess next week I'll be replacing all the uppers, the tie rods, my blown bilstein shocks (also around 40k on them) and all new strut/shock mount since those are shot too. Thsi shit never seems to end.

The way you tighten the control arms has an impact on how long they last. They are suppose to be tightened when the suspension is loaded. Tightened in the position that they would be when the wheels are on and the car resting at it final ride height, not as the car sits on jack stands.
With the control arms hanging down when tightened the rubber inserts have a constant strain on them when they are moved into their normal resting position (when the car is sitting on the wheels).

onemoremile
03-19-2007, 08:04 AM
^^ Exactly right. The distance between the edge of the upper plate and the upper control arm should be 2".

tunerb5
03-19-2007, 08:10 AM
so what ou are saying is that I should put a jack under the lower control arm, and jack it up before I completelly tighten the nuts?

ShawFM
03-19-2007, 04:08 PM
so what ou are saying is that I should put a jack under the lower control arm, and jack it up before I completelly tighten the nuts?

Yes jack them up to the nomal ride height (what you have it set to).
While the car is resting on the wheels, with ride height set on your coil-overs measure from the fender to the center of the the axel bolt (as a reference point). Then jack your car up change the control arms and while your car is still on jackstands raise the assembly to the same height you measured, before the final tightening of the control arm bolts. [race]

LateraLex
03-20-2007, 10:00 AM
This is pretty interesting I've never heard this. I have my mechanic do control arms out of sheer laziness, and he always tightens them on the lift. They do fail frequently, I wonder if this is part of the problem or just a coincidence.

Militant-Grunt
03-20-2007, 10:04 AM
Replaced mine last week. Got the 300 dollar kit off ECU tuning. Still need to replace one of the lower control arms, its throwing my allignment off since the uppers are so stiff.

ProOnThaSnow
03-20-2007, 10:10 AM
I think I am gonna have to go thru this soon. Whats the best way to tell if they're shot on these cars? I know my tie-rods are on their way out. Theres a little play in them, and I'm pretty sure it is them Squeeking when I am stopped and turn the steering wheel (no biggie, gonna replace when The car is lowered) but if I am in there I may as well repalce the control arms if they are in fact bad. The bushings in them look like they're in decent shape, and its not making the squeaking noise when there is suspension travel like my buddies A4.

ShawFM
03-20-2007, 12:10 PM
This is pretty interesting I've never heard this. I have my mechanic do control arms out of sheer laziness, and he always tightens them on the lift. They do fail frequently, I wonder if this is part of the problem or just a coincidence.

Good chance that is why they fail so frequently.
Without going into a long winded explanation.
Think of a clock with the hand traveling between the 1 and 5 o'clock position
If you tighten it in the 3 o'clock position it will deflect no more than + 2 or - 2
If you tighten it in the 5 o'clock position it will deflect +0 and -4 greater deflection in one direction will cause more strain and quicker failure.
That is why it should be tightened at the normal resting ride height.

Tiluleshpingen
03-20-2007, 12:40 PM
would the Febi-bilstein Controll Arms from ECStunning be a better replacement for the OEM ones?

tomustang
03-20-2007, 01:16 PM
My front uppers are shit again. I've aleady replaced them about 2 years ago. I maybe have 30-40 k miles on them and they are already shot. The car is slammed and I guess it shows. [headbang] . Guess next week I'll be replacing all the uppers, the tie rods, my blown bilstein shocks (also around 40k on them) and all new strut/shock mount since those are shot too. Thsi shit never seems to end.

the Bil's have a lifetime warranty on them

Daft
03-20-2007, 01:42 PM
http://www.hostdub.com/albums/turbo90awd/Upper_links.gif


Notice the measurement labeled "A"? That measurement is 47mm. It must lie between the tip of the bracket and the center of the control arm. I recommend doing the longer straight control arm first and then do the shorter curvy one second. I just lined the head of the curvy one up with the straight arm to set it to 47mm. When you re-attach the strut to the bracket, make sure that the mounting cup on the strut that hold the base of the spring (wider part with little slots in it) faces towards the inside of the car. Otherwise, it can rub the wheel bearing housing under load.

When you put the lower control arms in place, the arms will be in a downward position because there is no weight on the cars wheels. The shop manual clearly states that the bushing ends of the lower links must be tightened when the links are in a resting postion. They recommend putting the car on it's wheels to do this. Since I have a lowered car, I can't fit under there when the wheels are on the floor.

So.........

I put my floor jack on the bottom of the wheel bearing housing and jacked it up until the center of the wheel hub was at it's normal height. (measure before lifting the car) Then I went under the car and torqued the lower link's bushings down. The reason here is that the bushings are rubber and they are supposed to have elasticity in both directions (up and down). You are setting the normal height so that, when the car is parked, there is no tension on those bushings. Remember when I told you to set the upper links to 47mm from the bracket tip? That was the same thing.

One last item to keep in mind here, these arms fail in two different ways:

1. inner bushing noise
2. dried out or loose balljoints

The settings I have listed above have absolutely NO effect on balljoint failure. In most cases, the balljoints fail in some way before the bushings become noisey.

For my upper arms, I got two years out of the first set. ECS gave me new ones last year.

For the lower ones, I got about the same but, ECS wouldn't give me new ones. For now, I pumped fresh grease into the balljoints with a special syringe just to keep them together.

onemoremile
03-20-2007, 02:12 PM
Nice work Brett. That is the illustration I was looking for. I use a piece of 2x4 cut to 2" long. I slip it in there as a gage before tightening. I use the 2" dimension for stock height (winter mode) and use the 1.5" dimension for lowered height (summer mode). For those that don't know, a 2x4 is actually 1.5" thick.

ProOnThaSnow
03-20-2007, 02:44 PM
Wait...

Wouldn't that 47MM gap be ONLY for stock height vehicles? And another question I'm wondering is if there is a difference between even non-sport and sport suspension? I know it wouldn't be much, but there would be a difference, you'd think.

Whats the best way to keep these control arms good to go? Its kind of ridiculous that you'd have to replace them every couple of years.

And onemoremile what suspension do you have on your car in summer mode? as I am going to be replacing my control arms when I get around to lowering the car (as soon as my shocks come in), if I could go by your approximation it would save time. That is assuming you have a similar/same suspension setup for summer.

onemoremile
03-20-2007, 02:52 PM
I run stock sport suspension in the winter and have run KW V1 coilovers in the past. I don't currently have summer suspension. When I did I ran them anywhere from 1-2" below stock sport height. 1" below was the best for both handling and ride quality.

If you are swapping suspension then you can set the upper control arms on a workbench. They are part of the strut subassembly that comes out of the car along with the upper strut plate shown in Daft's posted illustration.

Tiluleshpingen
03-21-2007, 12:15 AM
would the Febi-bilstein Controll Arms from ECStunning be a better replacement for the OEM ones?

O k no one is going to answer this?[:(]

andernalin_junk
03-21-2007, 12:19 AM
i hope it will be ... i'm waiting for them also

Tiluleshpingen
03-22-2007, 11:38 AM
bump