mrtoofay

Hi Folks.

As the titls says. I have a 2016 GL350 that has recently developed a sagging problem. It's usually overnight, or over the course of two days. I would come out from the garage and be greeted by my car that's slammed in the back. It would rise back up after 20seconds of starting the car and everything would work fine. I understand that if I have a bad airbag in the back, it would leak and sag. But both side going out at same time? Or did something else fail? The fronts are doing fine.

Also, every 3~4 months, I would get a check coolant level in the morning. It only takes a cup or of coolant for the message to go away. I took it to an indie and they said it's heater core leak. Since they'll be taking the entire dash apart to gain access to the heater core, they are quoting me $950 to take care of it. Any write-ups on how to take care of that online? I searched, but my google-fu isn't that good.

thanks in advance.

chassis

Air suspension has been very extensively discussed on this site. Try the search feature.

Leaking heater core is a big disassembly job, $950 sounds like a bargain to me.

mrtoofay

I tried searching. Nothing involves both sides leaking overnight. It's all about one side getting replaced. If it's only one side sagging, then it seems like a fairly easy job to do by myself and I'll jsut get arnott bags. But since both are sagging, and then works fine when driving and parking for short terms, I am wondering if there's a leak somewhere in the system, or some type of a valve. Searching doesn't find anything.

Thanks for confirming the heater core pricing. Since both of my businesses are closed due to COVID19, just trying to save as much as I can, or prolong as long as I can, til I can open up again.

expl0rer

I have an x164. Had the same problem. Car stayed up over 2-3 days, but any longer without driving and it would squat in the rear, both sides. The sign about which side had the problem was the height of the corner. It was slightly lower than the opposite rear corner. It was more visible on level surface, but I confirmed with measuring tape. Consistently between half and one inch difference, lower on the leaking side. I would recommend the soap water test on both sides to hone in on the leaking bag.

Remedy was to replace airbag. I used Arnott. I can't comment on the x166 install, but on mine installion was ridiculously easy.

mrtoofay

Oh wow! That's exactly what my car's doing. I didn't realize that one side was a little higher since they both seem bottomed out. I always thought that if one side was not leaking, it'll still be able to hold that side up. Since I've seen GLs driving around with one corner slammed down to the ground. Just went out and checked with measuring tape. One side was 1/2" lower. Ording Arnotts now.

Thanks!

expl0rer

The height difference with mine was when the bags were inflated and the rear looked fine. Keep in mind that the surface must be level when you measure with tape. I did not measure for difference between the rears with the bags deflated.

Half inch is not much, it may be attributed to uneven surface where the GL is parked. But I still think your airbag is the culprit.

I only replaced one bag, though I am guessing the other might be a candidate sooner than later.

arsupisemnet

If you can afford you can replace both rear. Usually they go out at similar timing.
I replaced one rear on the left with Arnott. The one on the right i replaced with cheaper Chinese version from Amazon. So far so good.
Even small leak put to much work on compressor. So I would replace airbags as soon as you can. Unless you also want buy new compressor soon which happened to me because I ignored it for a while (had a leak in the rear) and once front airstrut gave up so does my compressor within a day or two.
Also I just rebuild front airstrut on the left as well. Bought Chinese airbag component only and swapped myself. Not much of the work.

mrtoofay

Replaced both rears with Arnott this past weekend. First one took a little figuring out, second one took less than 5min. Hardest part is actually jacking up the car and on jackstands. While it's not as easy as changing air filters, it's still not that hard. I was over thinking it. Here are some pointers that'd be helpful on my first try.

1. Don't need to remove any other parts like some videos suggests. Plenty of space to wiggle it out from top.
2. The air fitting nut is a little hard to reach if you don't have a small wrench. Go crazy with a plier if necessary, you're going to be throwing it away anyways.
3. Being a man, I have problems paying attention to the instructions that came with the airbag, almost gave up on removing the air fitting on the first one and wanted to cut the airhose. Pull the nut back (towards the top of the hose) you'll see a copper ring with a notch, use a flat screwdrive to open it a little and both the ring and the nut will slide right off. READ THE INSTRUCTIONS!!!!
4. The airbag was a little hard to pull off, turning it doesn't help. Either eat some spinach and go hulk on it, or do what I did. Pull the airbag down a little, and stick a decent sized flat head screwdriver in towards the middle, and just slowly work it down. It's just held up there by the white plastick clip, break it if you want. You'll be throwing it away like the air fitting nut.

It's been a couple nights. So far so good, no more sagging. Arnott's airbags seem to be made from better material than stock.