Hi All,
My 2012 GL450 has 78K miles on it. I came out to the garage the other day and noticed that the passenger-side front end was noticeably "sagging". After starting the car, it returned to normal and I actually drove about 200 miles that day. A couple of days later, it sagged again but definitely NOT as much as the first time. So, I suppose it's time to replace at least one air shock. A few questions for you all out there:

1. Can I use an after-market product (I see Arnott mentioned quite a lot)?
2. Can I replace one at a time?
3. Is there an error that would show on the display? I didn't get a flashing light, etc.
4. Is it possible that it's just the pump? If so, how would I determine that?
5. Is the car safe to drive?
6. What would be an approximate estimate from a local shop to do the repair? I

Thank you all so much, in advance.

 

they are air springs, not shocks. The whole front strut assembly contains a normal gas shock with an air bag spring on it.
1. Absolutely. Arnott or Bilstein sell complete front struts with new bags.
2. Sure. The other side will probably fail shortly thereafter.
3. You might get the airmatic error (white car with up arrow) when the compressor is tired from trying to pressurize a leaky bag. sag is primary indicator.
4. It’s Never just the pump unless the bags have been replaced prior and the OEM pump is still in there. Leaky bags will kill a pump in short order.
5. Depends. Bag may blow, or not.
6. About $1000 a side for the fronts. It’s a simple diy for the rear bags but slightly more involved for the fronts so do some research. Takes 15 minutes per rear spring and about an hour per front once you’ve done a few plus cost of parts.

 

In a lot of times, mine included, once the leaky bag is replaced it forces the pressure in the system that can then find the next weakest point to leak , 18 months ago, here in the UK, I had a faulty rear bag, the local specialist ( very trustworthy people that have helped me with my cars ) replaced that bag only to inform me the other rear was now leaking .
Them arghhhh, the fronts then needed doing. Very expensive at the time but my thoughts were I would be keeping the vehicle a long time and at least I know this is one thing that is now ticked off the list for the future.
You may be lucky but I thought it was worth letting you know.

 

I continue to be astounded by the level of knowledge from people in this forum. Thank you VERY MUCH for this info.
I haven't driven the car for three days and it's still in the upright position. I'm hoping that means the leak is VERY slow or perhaps what I saw that day was a harbinger of things to come. Either way, it sounds like I'll need to be prepared to spend close to $4K, eventually. I'm hoping I can do this over time. Friends of mine are telling me to sell the car but I've had no problems with it until now and it has just 78K miles on it. I'd much rather keep it, if possible.
After I go through this round of repairs, any idea what the next "big" item will be to go?

 

Thank you. Yes, this is what I'm most afraid of. If I could spread the repairs over time instead of all at once, I should be able to manage. If they all go bad in relatively short order, the car will be sitting in my garage for a while

 

I decided to spend the money on mine as I knew it would be a keeper, also I now know this is done so should not need doing again for maybe 10 years .
The next thing I needed to do was to replace the brake pipes together with the flexi pipes as well , bear in mind mine is 4 years older than yours and as it is a UK car we do suffer corrosion here as well.
I have had new discs and pads all round but they are normal items to need replacing anyway.

 

service your transmission on the recommended 40k interval - so next one is up soon.

Change brake fluid if you haven’t already.