G31 air suspension issue

[Lilu]

Hello everyone.

I'm writing this post in the hope that I can get some advice from more experienced people than me. The car under the spotlight is a BMW 520D Touring, 2019, 32k miles. The story goes like this.

A while back I've noticed the car in the morning looking a bit deflated on the back side but nothing major. Then after our holiday last year in September, when we came back after roughly 10 days, we found the car completely deflated on the back. Since then, every morning we find it in the same state. Once the engine is started, in 2-3 minutes everything is fine. The back side will get up where it should be and the vehicle is perfectly usable. 

So what we did was to go and check it at a garage. After a few hours they got back with the following conclusion:

Quote

After authorization we have stripped off covers from the compressor under the rear bumper.
From this we have pressured the airbags and have detected there is a leak in the air suspension where the unit itself meets the pipe from the compressor.
We have removed the pipe and cannot see it coming from any other area. So we re-fitted and tightened up the pipe to recheck and have confirmed it is leaking from this union.
This price is to supply and fit genuine parts from BMW.

The price offered was £1,030.45. This is for replacing NSR Suspension Airbag (OEM) & Pipe. 

It feels like the technical explanation is not sufficient. And my attempts to get more details over the phone have failed. They told me if there is a leakage on one side, both sides will deflate which I guess it makes sense assuming there is no valve or something in between the left and the right separating the channels . Fair enough. But how can the leakage be coming from the union between the pipe and the airbag and this to result in the need to change the airbag? How are these airbags built?

Has anybody encountered a similar problem before? Should I just accept their finding and go on with the repair? Initially they told me it would cost £110 to diagnose this specific issue, and they ended up charging an additional £110 because they needed more time apparently. But what they did in fact was to go through a full vehicle check on top of the investigative work, something that I did not ask them to do. So this, together with their inability to fully explain the findings, make me a bit reluctant to proceed with the repair. What do you guys think? 

I've attached the picture they provided.

 

[Kopfjaeger]

The Dealer price for the airbag would be of the order of £400-£500. The pneumatic tube would be less than £50. The balance would be labour. I'm guessing a 2-3 hour job and with dealer labour rates North of £150 per hour, you've got a 4 figure bill.

You can get Arnott air bags, which are OEM or better quality. Depending on the type  from about £200-£500 each.

If you replace just the defective bag and pipe, using an independent specialist, you should be able to get this done for roughly £500-£750?

Erring on the side of caution, I'd recommend swapping the OSR bag and check the other hydraulic line.  Doing this would increase the cost to circa £1100, as opposed to a dealer price Of maybe £2k?

You could save on the labour by going DIY, or if you're not confident/skilled, ask if someone here could help in exchange for being fed and supplied with 'liquid compensation'?

I've now checked Autodoc and they only offer Arnot bags at £500 each ( For my F07, the arnott versions are only £156!).

So unless you go with an alternative suspension bag supplier, you're only going to save on the labour by going independent as opposed to main dealer.

[Kopfjaeger]

If you look at the thread in the F series section about swapping the suspension air bags, you'll get an idea of what it is like...your G31 will be slightly different, though.  You'll also see who the experts are at doing this😁.

[Lilu]

Thanks a lot for your reply, @Kopfjaeger

Unfortunately, the price I got was from an independent garage. A 4.9/5 stars out of something like 500 reviews garage in north of Birmingham. It definitely didn't feel like a 4.9/5 experience. Apparently, the quote was done for Arnott and not a genuine product and Arnott seems to be more expensive than the OEM product. Weird. So it all depends on who you talk to at this garage. You'll get a different story every time 🙂 They will get back in the morning with a more detailed quote. It looks like I'm heading to BMW with this one. Rybrook or Sytner, we'll see. 

[Andrew]

Link to post above shown in screenshot 

The “experts” can remove a bag in less than 30 mins. 

BMW won’t entertain a fix of a connection as I think they specify that the connections are single use only. 
 

Yours might only need a short new section of pipe spliced in which bmw won’t recognise as a repair as there is no repair kit as a part. Or undo the coupling, cut a length of hose off reinsert it and tighten it back up. 
 

 

[Kopfjaeger]

That is unusual, in my limited experience with BMW. Independents are usually cheaper than main dealers. I've used RealOEM to look up the part and can see that your suspension 'bag' has an integral shock absorber, hence the high price. I've also checked the price of the base version of the spring on woxparts, which is a useful comparison for UK dealer prices.

So it seems your options may be limited. It would be interesting to see what a main dealer charges.

[Matthew]

15 hours ago, Andrew said:

Link to post above shown in screenshot 

The “experts” can remove a bag in less than 30 mins. 

BMW won’t entertain a fix of a connection as I think they specify that the connections are single use only. 
 

Yours might only need a short new section of pipe spliced in which bmw won’t recognise as a repair as there is no repair kit as a part. Or undo the coupling, cut a length of hose off reinsert it and tighten it back up. 
 

 

Don’t confuse the F11/F07 airbags with the air strut on the G31 and G32. 2 very different components and fitting is not the same. 

[Andrew]

15 hours ago, Matthew said:

Don’t confuse the F11/F07 airbags with the air strut on the G31 and G32. 2 very different components and fitting is not the same. 

Good point.

Means it an even more expensive fix then... All in the name of 'progress'.

[Lilu]

Meanwhile, they got back with another quote: £750 down from £1030. This is for one airbag. Very unprofessional approach and frankly, pretty dodgy. It looks like they were counting on my ignorance. Anyway, I booked the car for an investigation at a BMW official garage. Their estimate for replacing both airbags was £1360. So I'll go with that if necessary.

Lessons learned.  

[Kopfjaeger]

Based on strut costs of about £500 each, that equates to about £360 for labour.  In my area independent labour rates are £100 per hour, with main dealers double that.

So unless you can do the work yourself, no real alternative to save any money.

It sounds like you've been unlucky. I'm guessing the previous owner must have transported, some really heavy stuff, that contributed to the early demise of one of the struts. As I wouldn't expect to have to replace that kind of component after 32k miles.