Hi,

This is my first post, but having just finished a front end Arnott air spring install, with Bilsteins, I thought I would share some experiences (not sure I would call them tips, but I'll try). There is an excellent guide on air spring replacement here, and I'm not trying to recreate it - but for someone who had not done Audi suspension work before I thought there were a couple of steps that could use some color.

There are many accounts here and at other sites that this is an easy job for the DIY-er, and I suppose it is do-able. On a scale to 10, if changing a tire is a 0.5 and a brake job is a 3, I would call this a 5. Note that my 10 isn't a transmission or engine rebuild - that would be a 15 or 20 for me. I would do it again if I had to, but it took me about 8 hours over three evenings - not counting parts runs - and I ended up buying about $350 in tools, of which I didn't use about $100 worth and will return.

So, in order of uninstall/install here were the gotchas.

1. Pinch Bolt: I read multiple accounts of this challenge, and soaked it with PB Blaster for a few days before the job. Tried to remove it with a breaker bar, but saw the bolt head turning but not he bolt threads turning - and stopped. Broke down and bought an impact wrench (FYI - a decent home nailer grade compressor will run an impact wrench. My DeWalt 200 psi, 5.1 CFM did fine. I was surprised). This seemed to be the way to go. If you haven't used an impact wrench before, and I had not, you have to hold there and run it for awhile. Like 60-90 seconds. Then the bolt will move 5 degrees. Then 10. Then finally come free.... Initially I only tried for 15-20 seconds at a time, and it didn't work at all. It seems to require the persistent effort to break free.

2. Strut bolt was easy to remove the nut from, but the bolt wouldn't come out without dropping the lower control arm (the one with the ball joint that had the nut below the hub). The ball joint was easy to remove the nut from, but not to free. I tried jacking up the hub (stupid idea). I hit it on the side with a 16oz hammer. No effect. I sprayed and sprayed with PB Blaster. No joy. Finally I rented a front end service kit at the local auto parts store. Not one tool in the set was any use at all. So I bought a decent 4 pound hammer (the largest at Home Depot), but the nut on the ball joint until it was even with the end, and hit it once. Just one. Came right apart. Same on the other side.

3. Upper control arms - I tried to free those with a pickle fork ball joint tool. Big mistake. Tore the ball joint boots and ended up replacing the upper control arms. (It turns out the bushings were cracked, so it needed to be done anyway - so I tell myself.) I tried the front end service kit tools - nothing fit. Wailed on the arms with the hammer - no joy. But a cold chisel (blunt, round tip) and the hammer and a couple of good whacks to the bottom of the studs got them free. They had, of course, been soaked down with PB Blaster first.

--- For me recurring the lesson seems to be: don't be afraid to whack on the components with a 4 pound hammer. I was nervous about this, but had I gone for the hammer first I wouldn't have torn the ball joint boots. (I take no liability for the massive damage that you may cause to your Allroad. I'm just some dude on the internet, not a tech, not a good mechanic, not a mechanical engineer.) ---

4. Air spring mounting bracket (?) - the big aluminum piece that holds the upper arms and the air spring. Those aren't Torx screws. They kinda look like Torx screws. They aren't. I know, because I just bought $75 bucks of Torx drivers at Sears, none of which fit. It's a 12 pointed, or triple square, fastener. 8mm. I found one at my local auto parts store. And the inside doesn't really clean up to perfection. I tried degreaser, mineral spirits, dish soap, etc.

5. Upper o-rings. I thought Arnott had sent me the wrong size. The old, flat, un-reuseable o-rings from the Audi springs seemed to fit better. I went to the dealer, and paid $84 for two air spring install kits to get the 'proper' o-rings. Guess what - the same size. They seem slightly too big, and wouldn't stay flat. I tried warming them up to 80 degrees to see if that made a difference. Nope. This is where the 'lubricate the o-rings' step is important. I was using spray-on white lithium grease, which isn't thick enough. You need the paste type lithium grease. The grease sticks the o-ring down in the track and then it will stay flat so that you can bolt it up to the carrier or mount. It took me awhile to figure this out....

6. Air line fitting. Arnott sends a new one along with the spring. It's a brass screw plug with a collet. I hate to shout, but the COLLETS ARE VERY FRAGILE! Why did I have to yell that? well, I broke the collets taking off the old ones and putting on the new ones. They DON"T BEND. They break. The dealer charged me $43 dollars EACH for new fittings. That's about 1/6 of the price of the air spring from Arnott. I found a post from Ex-PzKW Cdr where he said that he cuts the line at the fitting, and there is enough air line to do that. I cut the line just above the collet with a razor knife, and then the new one slid on without breaking - but it's a very tight fit.

7. And installation is the reverse.... no. Not really.

7a. Getting the lower ball joint back in the hub. I jacked the hub up and down, turned the steering wheel back and forth, tapped with a rubber mallet. To be honest I'm not sure the magic combination was. I think I had the wheel turned about half-way in the direction of the side of the car I was working on, the hub medium low, and managed to get the tip of the bolt in the hole. And then it just went in as I jacked up the hub, no problems. But I wrestled with it for about 15 min to get there. The second one was no easier. I think it's just a 15 minute threshold.

7b. Upper control arms - they didn't want to go back in. Tried tapping, etc. Took them out, used WD-40 and a battery terminal brush and cleaned the inside of the pinch joint, coated them with anti-seize, and on the first side both went in with just a little persuasion. The second side, the front arm was no problem but the rear wouldn't go. I finally used a wood working clamp from the slot in the front of the hub carrier to the arm behind the ball joint to put pressure on it, and tapped with a mallet. It finally dropped in.


That's it - I'll report if there are any other issues, but I'm not expecting any. Sorry for the lack of photos - I didn't want to expose my camera or cell phone to the grime on my hands.



Peter

 

Great write-up which everyone needs to read when installing replacement air springs.

Pay particular attention to the air line fitting collet description. And if you ever work on the air compressor or the air distribution body, the same warnings apply to their air line fittings.

 

I wonder if time and exposure makes these harder on some cars? My car is a 2004 and only had about 45K when I did my fronts although it does get used in winter and they do salt the streets around here all the fasteners came out with just a normal amount of persuasion and lubrication. The first side took about 2 hrs as I felt my way along, the second about 30 min cause I knew all the "tricks" needed to get it all undone. I also used a 3lb hammer on the lower ball joint, one or two whacks and it popped right out. The critical thing to getting it back in again is to make sure it's going in straight, then it will fall right into place - I used the impact wrench to tighten the nut, but since it's a tapered shaft you don't really need to - if it turns on you just put some upward pressure on the arm till it pulls the taper into the hole, once it does it won't turn...

I also used the impact wrench on the upper pinch bolt, but mine came right out - I used some antisieze on it when I put it back in just in case I ever need to remove it again. The trick to getting the upper joints in and out is simple, take a cold chisel and tap it into the split (after removing the bolt of course) to spread it, then the joints will pop right out and go back in as easily.

I had no issues with either the small bolts or the o-ring.....the three bolts that hold the assy to the car can be a bit fun unless you have the right combination of sockets and extensions, but other than that it was pretty straightforward.

 

I snapped off the passenger side pinch bolt, then remembered you could remove the shock without worrying about it, we were able to unbolt the lower shock bolt, and the upper three bolts and swing the bottom out and undo the inner upper control arms, it took some patience but no big deal really.

everything was smooth sailing until the air-line reattachment, I followed the arnott instructions to the letter 'do no remove air fitting from shock' in particular, but of course when the system charged the air hoses blew out on both sides.

I took the fittings out and voila, no collets. I took the old ones and pur them on, they split in two but i put a little oil on them and was able to get it all in and it seems to be holding on level 4.

time will tell, but a fairly easy installation marred by poor implemetation.

too bad.

 

I wonder if the GenII air springs use a different method of attaching the airlines than the Gen I?

A couple guys have mentioned using the collets that were on the OEM air springs, the Gen I's that I installed did not use this type of fitting, rather they use the kind that has an o-ring seal built in - those do not have a nut that you tighten up over a ferrule like the OEM's do - you simply push the line into the fitting.

 

No all the air springs have the same threaded port for the air fittings. When I put Gen II's on the front of my car I did not use any of the Arnott fittings; I just re-used the OEM fittings with no problems.

 

[QUOTE=allroaddave;24141895] The trick to getting the upper joints in and out is simple, take a cold chisel and tap it into the split (after removing the bolt of course) to spread it, then the joints will pop right out and go back in as easily.

QUOTE]


Every Bentley for every Audi I've ever owned (4K, 5K, 200q20v, V8, S8, Allroad) says to NOT do this.

 

no need to even touch the pinch bolt - leave it alone

Lower strut bolt will come right out too...just find the "sweet spot" and it will clear the lower control arm

 

Hi guys - I'll be replacing the passenger side airbag in the Allroad this weekend. Can someone post the link to the DIY.

Thanks for your notes - will consider these when I do the job.
I replaced a CV joint boot a few months ago...many similarities I would think.

 

[quote=Kneale Brownson;24157627]Wonder why?

Not having the benefit of a Bentely manual, I did it in ignorance and it worked just fine - of course you only need to apply a little bit of pressure - you don't drive it home! All you're doing is re-aligning the bores of the two pieces by spreading it slightly, then the pin slips right out.

Maybe they're concerned people will spread it too far and split it, or drive the cold chisel into the pin and mark it?

I've done this for 40 years on lots of cars with no adverse effects, wonder what they're concerned about on the Audi?