DA8

I am replacing my upper control arms next week. Going to have the dealer do it, but have been reading up on the procedure in the Bently considering doing it myself because I do not trust the dealer has the actual tenacity to follow all the proper steps.

Bently says the procedure involves removal of the air strut. I have not heard anyone on the form say that. But I have read a few post on ride hieght being off. The air strut is placed in a vise with the control arms still attached then you swap them out (or fix the bushings if that is your route). To remove the air strut you have to disconnect the linkage for the ride level sensor from the lower control arm. You also have to remove the air pressure from the air strut by removing the air connection.

This has two effects which Bently says you have to correct. 1) is you have to put pressure back in the air strut(this part confuses me, I think it is done through diagnostics to a control pressure). 2) you have to perform a ride level adjustment with the diagnostic tool called "control position programing".

I have read a few post about this ride level change after the control arm replacement and I can't help wondering if it is due to improper procedure failing to perform those last 2 steps, likely because the air strut removal was done incorrectly. I have read a whole bunch of post on replacing the control arms or bushings and have not heard anyone talk about removing the air strut. This is either because they are not doing it themselves and don't know that it was removed or maybe they did do it themselves and found a way to do it without removing the air strut. I would like to know more about what procedure people used if they did it themselves?


Also BTW, according to Bently the control arm change is done as an intermediary step between removing the air strut and reinstalling the air strut. When the air strut is in the vise you swap out the control arms. When you do this you adjust the angle of the control arms by measurements with a ruler then tighten to torque. Then you reinstall the air strut. This addresses the comment that the control arms get the final tightening to torque with the car weight on the tires (not according to Bentley).

The air strut removal/installation page is on a separate page from the control arm page which defers you to go to the air strut removal/installation page for instructions on removing/reinstalling the air strut. The air strut page has to be cross referenced which could be the reason why the instructions adjust control level and fill the strut with air get missed. Some mechanics may do it so much with non air strut cars they think they know what they need to do and fail to follow that instruction and actually believe they did everything right. They they assure the customer everything is fine to cover their tracks. Their interest is to get you in and out for the time they quoted and not have any rework.

How do you ensure the dealer follows proper procedure?

mishar

If that you just described is the procedure I would make sure that my mechanic does not follow it.

There is no need to remove strut or anything else, except wheel, of course. It is very strait forward procedure. Only little trick is to tight bushings when suspension is under load and at the normal height. Easiest is to lower it to a support underneath lower arms close to the wheel.

MP4.2+6.0

Dealer did my D3 under warranty. From my C5 experience with it, the possible problem is "Art in Engineering" decided to install the bolts to make it easy to build the cars on the line when the whole subassembly with subframe, motor, tranny, shocks, and all is just lifted up and in. But on the C5, they have one of the upper bolts "backwards" for later normal maintenance. The C5 4.2, as well as the later D2's with the aluminum front suspension are very similar to the D3 set up, other than conventional steel springs.

Long story short, either you manage to force the poorly placed bolt out, or you just cut it with a demo saw (or an air grinder tool) and then put the new one in the reverse way. Otherwise, yes in theory you have to get the whole strut/spring/air unit out of there to pull the bolt straight out. Takes like 10 minutes per side to deal with the stupidly installed factory bolt if you just cut it, instead of hours incrementally to remove the strut units. And standard Audi maintenance is to replace any of these suspension nuts and bolts when pulled anyway, so the new part is already on hand. I expect the dealer guys do the grinder tool method if the D3 bolt is still inserted the same badly thought out way at the factory.

mishar

I agree that it is stupid, but as that is usual on Audi I didn't pay any attention. Just force it out or release the strut mount a bit and it is out.