This is my first time contributing to this forum. I specifically sought out this topic to confirm my suspicions that this is a widespread problem.

I have a 2014 G550 with 55,000 miles. Original paint without any customization. I have been the only owner and started noticing paint blisters around the windshield just now after five years of ownership. I live in Chicago and deal with a considerable amount of snow and salt during the winter months. It is garage kept.

I am in the process of communicating with the dealership, MBUSA, and the paint & body shop that the local MB dealership sub-contracts to.
The paint & body shop said they see this problem regularly with this model G wagon.

Attached are some pictures. Hoping to help JD101B with his research

 

SUGGESTION:

In the interest of helping older model G Wagon members better understand where the rust issues are and what Mercedes has done to correct them I propose we use pictures of the new 2019 and 2020 models as a comparison.

For example;

1. WINDSHIELD - The new models no longer have a rubber seal to hold the windshield in. So water that was being trapped under the rubber seal is eliminated.
2. As Surge pointed out, it seems that there are zinc coated bolts, hinges and spacers between the body and the actual hinge on the rear door hinges along with a waterproof grease on the pins.
3. DOOR AND REAR HATCH HINGES - Having read all of the posts here I am thinking that the rubber boots around the door hinges and wiring harnesses are water retainers on all models new and old.
4. SIDE WINDOW RUBBER SEALS - Another potential rust area. If you pay careful attention you will see water running out from under these seals after a rain or wash as you dry the car. so determing where it is entering will help develop a rust preventative solution.
5. MB SERVICE AND INSPECTION - I think checking with your MB dealer mechanic or service writer would be a great source to obtain blank copies of the periodiic inspection reports and check lists that MB technicians use on G Wagons in for service.

To be sure, MB uses customer service and complaint feedback to continuously build a better mouse trap in the new models. So we have an opportunity to learn what they already know and what ther correction processes are for these issues.

I have a 2020 G63 Wagon and would be willing to take pictures of various areas to be used for comparison purposes to aid in developing solutions.

Regards
Jerry

 

I don't doubt that the new models are better. But I'm still rather incensed that ANY Mercedes made withing the past quarter century has any kind of rust problems, and I'm particularly annoyed at Mercedes' unwillingness to admit these problems. And I really want to get a new G, but I also feel like a bit of a sucker giving them more money after the extremely well documented, widespread G class rust issues.

 

I’m not making excuses for Mercedes; but it’s interesting that you said “within the last quarter century”. The last gen G is a 40+ year old design! It’s well known for not having been altered other that internally and powertrain since its inception nearly 50 years ago.

I also wouldn’t call the rust issues “widespread” by any means (but I don’t want to argue) - just stating that in all my research before I purchased and while on the wait list for ~4 years, it never camp up.

In summary, the previous G is an OLD design. Think of what computers were like in the 70s. And design has changed drastically due to digital innovation.

 

Thanks for the post.

I would give the ENTIRE truck a look over. Right after Mercedes corrected some of the rust issues on mine, I discovered more underneath the front windshield. Mercedes wouldn't touch it. Make sure they address EVERY problem the first time...they won't even consider fixing these issues a second time.

It's good to hear that a body shop admits this problem is widespread. It further confirms what I already know.

I'm seriously thinking about passing this on to a lawyer for a class action. There are simply far too many documented cases. I'd be happy if Mercedes took my truck, stripped it down, and redid the paint with a new and better paint. I'd be satisfied if they fixed the remainder of the spots.

Anyways, if you plan on keeping the truck and want to keep it as rust free as possible, I've devised a system to inhibit rust:

~In your garage, place a large dehumidifier - figure out the approximate cubic footage (length X width X height) and get a dehumidifier rated for a space AT LEAST 50% larger - mine is rated for a space twice as large. Purchase a humidity gauge and make sure the garage never exceeds 15% humidity. This will help draw excess moisture out from under the car and behind seals.

~Get seven good sized fans. Yes, seven. You want three placed under the chassis, blowing air up into the rear, middle and front of the truck. You want one fan blowing on the bottom of the front and rear doors, one blowing on the windscreen, and one blowing on the rear doors around the hinge area. Along with the super dry air, this should help to remove excess moisture in hard to reach areas. Run them whenever the car is parked, even if the car is dry.

~Perform an undercarriage treatment with LPS. LPS is a miracle water repellent. What makes it brilliant is that it doesn't trap water (it drives it from the metal) and while it is oil based rather than a paint, LPS is amazingly resilient and lasts for at least six months (even with tons of underbody spray). It's the next best thing to corrosion resistant metal. It's that good. Also, consider applying LPS behind window seals. The same idea applies.

~Learn how to properly wash and detail your truck. NEVER put it through a car wash that uses brushes. If you need to use a touchless wash because you don't have time, make sure to properly dry the truck ASAP. Try to remove road salt ASAP. A solution of baking soda and water is a great way to neutralize salt. If you don't apply LPS to your chassis, consider a two step process of high pressure soapy water, then a low pressure application of baking soda and water. The baking soda will coat the chassis and help neutralize salt. Don't apply baking soda at high pressure as it will act as a minor media blast (i.e. sandblast it).

I'd like to discuss your rust problem further. Could you send me a PM?

Best,

J

 

Age isn't an excuse. If the car was prone to rust, Merc should have fixed it or not sold it. They could have used more rust resistant alloys, better paint, better galvanization, etc. The fact is, they chose not to.

If their motto is going to be "The Best or Nothing" they need to act like it.

 

Rust under the front windshield on w463s are a major problem. My 2010 had a serious issue that MB took care of out of warranty Get an estimate to repair the issue from them and get MB to agree to correct it. That is what I did. When they took off the seal they uncovered a massive issue that was fixed by MB since at that point they were agreeing to the out of warranty repair. Also check the sunroof surround/seal on top. And the roof in general. I loved my g55 and would have kept it if not for the fear of the rust issues. I live in a salt air environment but that really shouldn't matter much on a modern vehicle. One interesting note is that MBUSA has almost no mention of rust or corrosion coverage on their USA materials.

 

Do you have any pictures or documentation for that job they performed?

 

Do you have any pictures or documentation for that job they performed?

 

Sorry, I do not. I'm not a good record keeper. But I had those exact little bubbles popping up under the driver side front window. Ignored them for a year. They started to spread. They ended up needing to weld in place a whole new section of the front windshield. Required exact welding specs from MB because it was such a key structural component of the G55. Entire job was probably over 10k but I never did get a chance to see final bill. They pretty much told me this was the only out of warranty fix I was ever getting and may have even signed something to that effect. I forget the time but I think this was 2015 on my 2010 G55. Traded it back to the dealer when I bought the new G63 since I didn't any liability on a private sale.

 

Just another data point, and i wish i took pictures of this but i looked at 2018 G63 yesterday and it too had rust staining/marking under the windshield gasket at the corners, and around the cargo door hinge gaskets. Now mind you, there were no bubbles, just rust coloring on the paint in those areas behind the rubber seals. This was a white 15K mile car and was absolutely mint. dealer was asking $114K. CA history with some trips to Lake Tahoe possibly, judging by the Carfax. I was a bit shocked to see this pop up on such a low mileage CA car, to be honest.

 

Not sure where in CA the car was, but wouldn't be surprised if this 63 was kept along PCH in Malibu. Plenty of G's there with rusting.

 

Negative. This is a Northern CA car in Sacramento. Hot and very dry up here with no salt exposure.

And since we're talking, the reason I noticed this thread initially is because i was looking at another car - a 2006 G55 that lived its whole life in Salt Lake City, UT and was dealer serviced there with extensive records. This particular car was priced on the lower end due to mileage (121K) but it looked very clean in the pictures and was being sold by MB of Draper, UT. Upon further inquiry, after i had placed a deposit on it, they disclosed that the car had rust on the bottom of the windshield frame, around the side windows on the passenger side (by the gaskets), the rear cargo door hinges and along the bottom of one door sill. They agreed to repair these areas and made an attempt to do so. While i asked for additional photos of the undercarriage other areas on the car - such as the top and bottom of the rear door, roof drip rails, and rear corner seams, they did not get them to me until after the first round of rust repairs had been completed. Long story short, they thought everything was fixed, but low and behold, their body shop missed the cracked rear corner seams, and more rust on the top of the rear cargo door. At that point, i passed on the car as I realized it's probably a rust bucket and chances are when rust is so prevalent on a car, there are other spots that I couldn't see that also had rust. That car has sold so hopefully whoever bought it wasn't unpleasantly surprised.

Seeing that the last batch of these cars have similar issues with cars built decades earlier, i can't help to think that MB is well aware of the problems and chose to ignore them as they are inherent to the design of this car. The windshield molding for example, has no easy fix. The only viable improvement would come from redesigning the windshield frame to accept glued in glass (which they did on the new ones). The same goes for the hinge design, and other problem areas that would've required considerable re tooling at Magna Steyr for a car that is relatively low volume and generally speaking was probably a cash cow for MB as it was, rust prone and all. These things have been rusting for decades, and the cost benefit analysis to implement design and manufacturing changes probably came out on the wrong side of the consumer. Any repairs demanded by original owners under the warranty period were likely handled to preserve customer loyalty. All others were and are probably not a concern to MB, In fact, most people buy this car for its image, build quality be damned, and would probably purchase or better yet lease one knowing full well about the rust issues. My $.02

 

More adventures in G550 rust.

Today I washed the truck, taking care to carefully wash known rust spots. Normally, I apply a thin layer of WD40 to the exterior of the weather stripping around the windows and the hinges...today I got the idea to inject it directly behind the weather stripping...using the provided straw, I lifted the top corners of the front window weather stripping and applied the WD40...a few minutes later it begun to leak out of the middle bottom of the weather stripping (roughly in between the two windshield wiper motors). Interestingly enough, it leaked out of a few other areas where there was no apparent rust. I got the idea to look behind the stripping in these areas and there was A LOT of rust...my fingers were brown after just a few seconds of prying back the stripping.

Eventually I'll get around to repairing the damage (thanks MBUSA - "the best or nothing") but for now, I hope that the WD40 will inhibit or at least slow the progression of the rust. I also applied WD to all door hinges (I wrapped them with a towel before application to prevent overspray), the front antenna surround, the moon roof surround (I never open it), the rear XM radio antenna and the rear view mounts. I always regularly treat these areas with WD, but today was the first time I injected the WD behind the front windscreen glass. I'd suggest that all G owners do this. Even with my extensive rust prevention techniques (parking the car in a garage with fans and a heavy duty dehumidifier) I haven't been able to prevent all rust...

Also, I've noticed that the paint on two of my wheels is bubbling. It's really amazing just how prone to oxidative damage this truck is. My ML with similar miles has none of these issues. I've had Merc's with twice the miles and no rust problems...

 

If you ever pass by it again, get some pictures of the rust.

 

Maybe I missed something - on your 2010 G550 - are you the Original Owner - and if not - where/who/when did you buy your G-Wagen from ?

In Winter Salt Areas - especially Winter-Salt-Metro-Areas - G's have had problems - and frankly that is no surprise to any Mercedes enthusiast - and the strong part of G-Wagen character are the mechanical's - the unfortunate part og the G-Wagen character - rust in rust prone areas - is shared by "many" classic "outdoor classics" Wagoneer's - FJ's - classic Landcruiser - Defender's .

What do you want to do with your G ? Are you going to have it repaired ? Keep it as is ? Sell it ?

As other's have mentioned - cosmetic body rust left unchecked will ultimately become structural rust - and frankly you don't want to go down that path too far.

Polling dealership's on "younger G's" to commensurate about Salt Problems really doesn't change path's for you - and to be frank - a can of WD40 is not really not any type of workable plan.

Best of luck to you...

 

LPS 1 Premium Greaseless Lubricant - this plan work work either..

 

So I've been following this thread intermittently since it's inception. Seems like there is credible evidence that the previous generation G is prone to rust. There is a some debate as to the level of susceptibility of having rust and whether or not certain measures actually work. I'm at 7500 miles per year, garage kept. Never leave my truck outside and pretty much don't go out if it's raining unless I have to. We have a place near the beach but hardly take the G there due to the salt air. My question is what is the best preventative measure to minimize the chances of rust? Coat the body without of course taking anything apart?

 

I really am trying to empathize with you @JD101b . Your 2010 G550 - you are not the first owner, and it looks like you noticed 2 small rust areas in 2018, so 8-9 years after it was manufactured. I’m not sure what is wrong with that? 8-9 years would create rust spots on most cars, at least in 1-2 minor areas. Especially without knowing how the car was treated and where it was located for the ~8 years before you purchased it.

You’ve also posted about this quite a few times, in various threads, (as I would have), and there haven’t been many replies — which tells me the problem is not that widespread.

Also, WD40 is hygroscopic, meaning it attracts water, and causes rust! It can be used to clean rust, but should not be left on the metal afterwards. You need an actual water repellent coating. WD40 also attracts dust and dirt, so it’s not a good idea for door hinges, for example.

My $0.02 - if you want to keep your 2010 - get it fully repainted. The body shop will repair the rust areas when it’s at the bare metal. It will look like new and will be rust free, probably for 10+ years if you care for it like you do.

 

it's just a material item. Not taking the G to the beach because of the salt air or because it's raining? It's not an old sports car with terrible ESP, it's a G. That seems a little overworrying to me (which I sometimes do until I become comfortable with a car). Every car will eventually rust a bit and when it does, you'll likely be ready for a new car anyway. One thing you could do is buy a power washer and extension for the underbody and do an underbody wash If you drive on sand and stuff. But these cars were made for "harsh" environments like beach homes and salt air.

 

I think rust is best looked at is a wear or maintenance item. The original G is about 40 years old - structural changes are not something that are easily done, so it’s not a matter of ‘rolling changes’.
The rust issues seem to be surface and minor. Has anyone heard of the frame rusting through?
Fixing surface rust every decade doesn’t seem like a big deal for a 40 year old design.

 

Doesn't the WD stand for "water displacement"?

Sorry, but there is no excuse for rust on a $100,000 car with 60k miles on it. There are 140 replies to this thread, including pictures from rusting last-revision models and a Mercedes body shop guy who says this problem is widespread. During a casual search, I found several sub-40k mile G-class vehicles with rust and posted the pictures to prove it. Find me another $100k car like that. Find me a $20k car like that. What is this? A last generation Dodge Ram?

My wife and I travel a lot for work (mostly to Europe, which is real interesting during COVID19) and I'm not sure if I should keep it and invest the money to repaint it (and undoubtedly fix chassis rust issues) or just buy the current generation and put this nonsense behind me.

 

It seems like they addressed the issues on the new Gen. I would buy the new one, as I did; but I realize it’s not an easy decision.
I think you’d get your money back if you repainted your current one, if you don’t spend too much on the repaint.

 

You can use LPS or WD40 (they have a rust inhibitor formulation) to spray behind the window seals, the door hinges, and behind the rubber gasket on the rear door hinges.

I'd treat the underside with LPS, which displaces water and inhibits rust. It is NOT a sealant, which means any moisture trapped under the oil is eventually expelled. Underbody sealants can trap water, making the problems worse. LPS stands up very well to prolonged sand and water spray. Some people say it lasts their work trucks an entire year, but I'd reapply every 6-months to be safe. You can also use a powerwasher to spray the underside with soapy water, then using a low-power setting, apply a solution of water and baking soda. The baking soda neutralizes road salt and promotes drying, again even in hard to reach/ventilate areas. The baking soda does leave a coating which does offer some short term protection against salt, but don't think of it as a long term solution as it will eventually wear off. Also, never apply the baking soda solution in a high powered spray, as it will act as a mild blasting media.

I park my truck in a garage with a large dehumidifier and seven (yes, seven) fans to help try the truck out - two fans are positioned at the front windscreen, three under the body to help dry the underside and two aimed at the rear door/hinges. I have a humidity gauge and try to keep relative humidity between 10-15%. This helps to draw moisture out of even tight spots.

 

I'd imagine the rust issues have been addressed as the current G is a clean sheet design.

Right now, between travel and splitting our time between our home and place in NYC for work, I'm not sure it makes sense to buy a new G.

Still, it seems that no new rust issues have popped up since I implemented my system of drying and protecting the truck, so maybe I'll just have the windscreen surround repaired and leave it at that.

Anyways, I didn't mean to be so curt with you before. I'm just a bit annoyed that a Mercedes of all vehicles has such poor QC (evidentially they forgot all the lessons learned in the 1996-2005 period).