Are Instructions on Fitting Control Arms Correct?

[SDHA4SLine]

I'm a little confused about the method of replacing front control arms, recently I read that the upper & lower control arm fixings should only be fully tightened when the suspension is under load at normal ride height. However looking at what I believe to be an online Audi workshop manual it looks like this is not the case. quote from manual for lower arms....
Bonded rubber bushes can only be turned to a limited extent. The mountings of the suspension links must therefore only be tightened when the suspension is in the unladen position

Am I misunderstanding the manual or is this the correct method?

upper arms

lower arms

 

[Cyrix]

Must be wrong as every other VAG workshop manual I have seen has said the opposite. Just think about it, if the bushes are tightened in the unladen position that are going to be constantly under excess tension when the car is on it's wheels.

I would use the instructions as a rough guide by the way, the upper arms are a nightmare.

The easiest way I have found to do the upper arms is do the following.

Remove Driveshaft Nut
Remove Caliper/Carrier/Disk
Disconnect ABS wiring loom at chassis end (multiplug under rubber bung)
Disconnect Track rod end
Remove lower shock mount bolt.
Remove 2x Lower ball joints
Remove the 3x 16mm bolts for the upper strut mount (in engine bay)
Remove hub + strut in one lump.

To remove the upper arms I usually do the following -

Remove nut from long bolt in hub, discover it's seized solid.
Spray it with some kind of penetrating fluid.
Use Blowtorch to heat up the hub, you will set fire to the rubber boots on the upper arms, do this for 5-10 mins while trying to turn the bolt, when it starts to move it generally gets tight after a few turns, wind it back in, add penetrating fluid etc. It takes forever with a wrench, I normally use an impact gun once I've got it moving to rattle it back and forth.

You can do it without removing the hub, but it's far easier to do on the bench.

 

[SDHA4SLine]

Must be wrong as every other VAG workshop manual I have seen has said the opposite. Just think about it, if the bushes are tightened in the unladen position that are going to be constantly under excess tension when the car is on it's wheels.

I would use the instructions as a rough guide by the way, the upper arms are a nightmare.

The easiest way I have found to do the upper arms is do the following.

Remove Driveshaft Nut
Remove Caliper/Carrier/Disk
Disconnect ABS wiring loom at chassis end (multiplug under rubber bung)
Disconnect Track rod end
Remove lower shock mount bolt.
Remove 2x Lower ball joints
Remove the 3x 16mm bolts for the upper strut mount (in engine bay)
Remove hub + strut in one lump.

To remove the upper arms I usually do the following -

Remove nut from long bolt in hub, discover it's seized solid.
Spray it with some kind of penetrating fluid.
Use Blowtorch to heat up the hub, you will set fire to the rubber boots on the upper arms, do this for 5-10 mins while trying to turn the bolt, when it starts to move it generally gets tight after a few turns, wind it back in, add penetrating fluid etc. It takes forever with a wrench, I normally use an impact gun once I've got it moving to rattle it back and forth.

You can do it without removing the hub, but it's far easier to do on the bench.

Thanks, not 100% sure if I'm confident enough to be doing this myself but investigating how to do this out of desperation due to garages letting me down & parts suppliers too.

It'll all be coming out as I've a lot of new parts to fit......
outer drive shaft cv joints
front wheel bearings
front wheel bearing flanges
front control arms
front & rear springs
front & rear shocks
front & rear top mounts
front & rear spring seats/isolators
front arb bushes & drop links
rs4 rear arb, bushes & drop links
May be more but I cant remember now!

Regards
Steve

 

[Cyrix]

Quite a lot of work, all fairly straightforward though. Just make sure you have the right tools to hand before you start.

The upper front control arms and rear springs are the only bits that will give you the biggest headache.

 

[SootySport]

I can only think the "Unladen position" bit is not having people, luggage inside the car when the nuts and bolts are torqued up. Maybe a quirk of translation from German to English.

If you do diy then you'll need heat, penetrating oil and a ball joint splitter.
I've had a look at my suspension linkage on the 2005 S4 and there is a lot of rusted nuts and bolts that are going to be a pain to undo. Start soaking the nuts & bolts in penetrating fluid a few days before you start and give them a spray every day.

 

[SDHA4SLine]

What's a decent penetrating oil to use? I take it wd40 is for wimps!

 

[Charlie Farley]

plusgas penetrating oil used to be my preferred one ,but, as per normal is no longer available and haven't really found anything that is as good, just try a web search for heavy duty prof penetrating fluid and you'll be spoilt for choice.

 

[SootySport]

Wd40 is nota penetrating oil, Plus Gas is popular, didn't know they stopped it. I use unbranded freebies from work.

Best ever in the world was Easol in a yellow cans and that hasn't been for sale for years but maybe re branded, worth searching out.

 

[ajax1976]

Other than the exposed threads I found penetrating oil on the arms pointless. Its a bimetallic reaction that causes all the seizing and issues, Penetrating oils won't penetrate or do anything with that. The biggest thing I found to help was to actually tighten the bolt or fitting first. This can stretch the bolt making it thinner thus breaking the bimetallic bond, you'll have to be carefull not to snap it tho.

 

[Charlie Farley]

Sometimes a sharp blow with a decent hammer can be just enough to break the bond between two seized surfaces, don't hit the bolt or nut directly or you will possibly deform the head etc, use a piece of metal in between thus transferring the shock instead of just wacking and deforming the bolt etc, I've found using a thick piece of ally of similar works really well and on old tractors there are some seriously stubborn nuts and bolts that are a sod to shift otherwise, just a suggestion from previous experience, I expect I'll get short down again in a minute anyway for this suggestion.
I've used my old vessel impact driver with an old socket attached to very good effect aswell.

 

[gary_a4_quattro]

Wondering if anyone has had experience of this tool ( or similar ? ) :



Speaking to an Audi tech I know, he said they had one (again or similar ) but it ended up still bending the bolt. I looks in the vid it makes the job a doddle, but who knows how well seized in that bolt was !?!?

 

[SDHA4SLine]

Looks remarkably like a copy of this one...


Except it doesn't have the pins to push out the ball joints. Just found it on amazon, it's £373. Think I won't be buying it!

 

[Charlie Farley]

maybe it would be a lot quicker and easier and safer steve to get the work carried out by a decent garage, more expense in labour cost but unless you are sure and confident you can do this work , leave it alone mate and ask yourself the question again, can I do this properly, if not don't start the job just get it done by a garage.

 

[SDHA4SLine]

I can do it, it's just I only have two days holiday left until January. All garages I've asked to quote for all stuff I've got to fit said its a (worst case) two day job. So for me it's probably gonna be four because Im and engineer and can't help but be real slow and methodical, it's engrained in my dna!

 

[gary_a4_quattro]

Looks remarkably like a copy of this one...


Except it doesn't have the pins to push out the ball joints. Just found it on amazon, it's £373. Think I won't be buying it!

Yup, sure looks the same, but as you said £373 is a fair chunk of dough. I guess if you're doing them day in , day out its a good investment. Mind you, look how clean everything on the car is, doesnt represent most peoples situation unfortunately

One thing I did notice though, the pinch bolt they remove (at 1:59 on the vid ) sure looks like the end is well n truly peined over, would that have come out as the end is munched !?!?

 

[SootySport]

I can do it, it's just I only have two days holiday left until January. All garages I've asked to quote for all stuff I've got to fit said its a (worst case) two day job. So for me it's probably gonna be four because Im and engineer and can't help but be real slow and methodical, it's engrained in my dna!

Wait till you get to my age, probably 6 days