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The rear door hinge is another point of corrosion. Luckily, there is a relatively easy way to get behind the metal. There is a removable plastic vent immediately to the left of the door on the driver side. If you pop it off, you can thread a long aerosol can straw up and down to spray both hinges. The spray pattern is pretty wide so coverage should be okay, just move the straw up and down to ensure maximum coverage:
And of course, there is rust on the inside of the driver side door (passenger side too but I didn't get a photo. It's hard to see here but it looks to be somewhat advanced. I'll need to take all the door panels off and remove any surface rust then treat with WD-40 corrosion inhibitor spray:
I finally managed to get one of the running boards off. Unfortunately, all three of the screws holding the bracket to the bottom of the running board broke off with mild-moderate torque. This was after liberal application of WD40. They were badly corroded and I will be replacing them:
As you can see the board does have some corrosion. I sanded it down using 120 grit paper + my trusty wire wheel to remove any loose rust. I gave it three coats of Rustoleum and the a coat of satin black enamel. I'm going to sand it down tomorrow with 400 grit and give it another two coats of enamel. Once I am done, I will spray all the closed channels with WD-40 corrosion inhibitor using my long-tube applicator to make sure I get behind the metal.
I didn't sand the entire board down the bare metal. Most of the paint was in okay shape, but I did want to remove surface rust and apply a rust-inhibitor primer. Plus, removing the board makes it much easier to apply WD40 underneath.
Speaking of applying WD40, once I removed the boards I found that all six holes for the bolts were completely open to the sheetmetal behind it. So, I took my trusty can of WD40 corrosion inhibitor, put the 40 inch tube in each one as far as it would go, and gave it a spray, making sure to pull the tube out while doing so to make sure all the metal inside was coated. The straw aerosolizes the oil pretty well so it should get everywhere inside these cavities:
This is one of the brackets before I dipped it in rust remover. The other two are in similar shape. I used a rust remover bath because these parts were in bad shape and it would be difficult to sand inside of them. Once I get them cleaned, I will hit them with a few coats of primer followed by some satin enamel:
I took the endcaps off, sanded them with some 400 grit (yes, only 400 grit) then gave them two coats of primer followed by a 400 grit sanding and two coats of gloss black. They look good so far. I'll probably sand them with 600 tomorrow, do another two coats of gloss black and then a coat of clear:
Here is one before and after (1st coat of satin black enamel) of the underside of the running board:
Forgot to take shots of the steel on top. I used some metal polish plus some "extra fine" steel wool to remove tarnish, caked on dirt (that wouldn't come off with soap) and corrosion (there was quite a bit near the end caps). It came out alright, though many scratches are still present. Unfortunately, because there is no easy way to remove the rubber stripping, I can't take my DA to it, so I'm stuck rubbing by hand.
WD40 is Not the right product for rust protection. It’s far too light to stay on for a long period. I posted an alternative above.
Yes, I did see that. This is a special formulation of WD40 called "corrosion inhibitor". It is a thicker and more viscus oil that clings to surfaces better than regular WD40. I have tested it on several exposed parts of the G and it has held up well over the past six months. Besides, most of the areas I am spraying are relatively protected from the elements (for example, inside of the doors, body cavities, behind the weather stripping, etc. Very littler dirty, water spray, etc will directly effect these areas.
Yes, I did see that. This is a special formulation of WD40 called "corrosion inhibitor". It is a thicker and more viscus oil that clings to surfaces better than regular WD40. I have tested it on several exposed parts of the G and it has held up well over the past six months. Besides, most of the areas I am spraying are relatively protected from the elements (for example, inside of the doors, body cavities, behind the weather stripping, etc. Very littler dirty, water spray, etc will directly effect these areas.
Ah, ok, good! I missed that it was a unique formulation. I just didn't want you to "waste" all of your efforts by using something that won't last long.
Ah, ok, good! I missed that it was a unique formulation. I just didn't want you to "waste" all of your efforts by using something that won't last long.
Thanks, I do appreciate that. I did make the mistake of WD40 initially (early last year) but I did test it on exposed areas and found it ran dry pretty fast.
After a good 20 minutes with the wire wheel and cup, the brackets are looking pretty good, but I think they need another bath in rust remover to get the pits and the hard to sand areas. Then there is the left and right running boards, one before cleaning and one after cleaning (and new paint).
Most of the bolts sheared off so I will need to replace them. They were completely rusted over. I'm going to get some galvanized replacements then coat them in Red n' Tacky grease.
One of the bolts from the running boards - the ones that didn't shear off were all like this - completely rusted through, seized and with stripped threads. I'll replace with galvanized bolts/nuts and pack them with hot n' tacky grease to prevent corrosion in the future.
I just replaced my running boards as my old ones were bubbled up and full of rust. I got replacement from https://www.ebay.com/itm/353459632393
They were perfect fit and arrived within 5 days. They come with new brackets and all hardware
Almost finished with the running boards. Used steel wool and metal polish to clean up the metal - it removed most haze and brought back some shine but deep scratches remain. The underside was sanded and resprayed with rustoleum primer and satin black paint. It came out looking pretty good - much better than before at least. I made the mistake of using the wire wheel to sand down some corrosion on the board that was more rusted. It left the metal with brush marks that showed through the paint. It's not terrible, but I should have used filler primer instead. Oh well.
The brackets took a LONG time to sand down. Even the paint which appeared to have no corrosion underneath did. I ended up removing all the paint. Here are the brackets ready for a rust remover bath.
I replaced all of the bolts attaching the brackets to the running boards with new galvanized hardware. The old bolts, rust and washers were completely rusted over. Some were so badly rotting out that they had partially disintegrated. I'm going to pack them with red n' tacky grease to add another layer of protection. Red n' Tacky is extremely viscus and not easily removed. It has great anti-corrosion properties. Only problem is that it smells terrible.
Aforementioned Red n' Tacky grease. You can use a caulking gun to apply it, but I use a rubber putty knife.
WD 40 "Specialist Corrosion Inhibitor" with a 36" long straw. This is how I get into hard to body cavities, under weather stripping, etc to coat it with the oil. The oil sprays out in a fairly fine mist and has an approximate three foot range.
I'm going to sand down the ends a bit more with a finishing drill bit then pack them with grease. I will spray the WD-40 down the channels to ensure that they are protected from the inside, too.
I found rust under my front windshield as well as on the upper side rails. MB is fixing it under warranty but they won't provide a loaner car. When I was discussing the issue with the factory rep he made the mistake of using the term "good willing the repair". I asked him how repairing rust on a 3 year old truck that was over $150,000 and still well under warranty goodwill. That pissed me off. We have what is arguably their most expensive vehicle and if not, damn close to it. Good will would be to have given me a new one. A warranty repair is bare minimum. There was also a small chip in the windshield that I hd repaired so I figured I'd have them replace it in case it got worse. $1100, oh well....
Im glad you're getting it repaired. I'd check to make sure there aren't any other areas before they start the repair. Get them to do everything now because they won't do it again.
Do you have any pictures by the way?
Originally Posted by jeffnnj
I found rust under my front windshield as well as on the upper side rails. MB is fixing it under warranty but they won't provide a loaner car. When I was discussing the issue with the factory rep he made the mistake of using the term "good willing the repair". I asked him how repairing rust on a 3 year old truck that was over $150,000 and still well under warranty goodwill. That pissed me off. We have what is arguably their most expensive vehicle and if not, damn close to it. Good will would be to have given me a new one. A warranty repair is bare minimum. There was also a small chip in the windshield that I hd repaired so I figured I'd have them replace it in case it got worse. $1100, oh well....
I found rust under my front windshield as well as on the upper side rails. MB is fixing it under warranty but they won't provide a loaner car. When I was discussing the issue with the factory rep he made the mistake of using the term "good willing the repair". I asked him how repairing rust on a 3 year old truck that was over $150,000 and still well under warranty goodwill. That pissed me off. We have what is arguably their most expensive vehicle and if not, damn close to it. Good will would be to have given me a new one. A warranty repair is bare minimum. There was also a small chip in the windshield that I hd repaired so I figured I'd have them replace it in case it got worse. $1100, oh well....
I found rust under my front windshield as well as on the upper side rails. MB is fixing it under warranty but they won't provide a loaner car. When I was discussing the issue with the factory rep he made the mistake of using the term "good willing the repair". I asked him how repairing rust on a 3 year old truck that was over $150,000 and still well under warranty goodwill. That pissed me off. We have what is arguably their most expensive vehicle and if not, damn close to it. Good will would be to have given me a new one. A warranty repair is bare minimum. There was also a small chip in the windshield that I hd repaired so I figured I'd have them replace it in case it got worse. $1100, oh well....
If you'd like I can go over with you all the known problem areas on the G, and discuss ways to prevent or mitigate it going forward.
I used 80,120 and 240 grit paper as well as a wire wheel, cup and "Metal Rescue" rust removal soak to remove the rust. The pitting is still evident through the paint, and I used a filler primer to mitigate it somewhat. Still, the metal is now clean and protected. I purchased all new stainless hardware (nuts, bolts, etc) and will pack all of them with the aforementioned red n' tacky grease before reassembly.
I should mention that sanding down the metal on the backside of the brackets (in the following picture)
was very difficult owing to the tight clearances. Seeing as I don't have a sandblaster, if I were to do it again I would soak them in a heavy duty paint remover followed by a rust removal bath.
About 5 months ago I noticed some small rust when filling gas for my wife (it’s her car). Then, I started to check the entire car and found about 8 - 10 more areas ie around the windshield, around the sunroof, some on other parts. I immediately took it to the dealer and ask them to convert the repairs. I bought this bran new G500 at Mercedes Benz Of South Bay in Torrence, California and have been taking the car there for service from day one and they never said anything about the rust - even though they claim a “multiple inspection” process every time you take the car for service.
The only way to take care of this is with a class action suit. It is extremely expensive to fix and the care are defective!!!!!!
Hi JD101b
Did MB take care of your rust issue? I have a 2008 G500 with rust and I'm trying to recruit folks that have rust issues with this defective body work from the factory. I'm in California where there is harsh winters etc. If you want to join a potential class action suit, please email me at beyondmediaproductions@yahoo.com Thanks
I had a 2010 G55. Had the rust bubbles under the windshield. This is a major issue. MB agreed to repair the rust when the estimate to do so was $2500.00. When they finally got the car in the shop and started the repair job it became clear very quickly that there was a lot more going on. The repair ultimately entailed welding a whole new frame around the windshield frame and required input direct from MBHQ on maintaining structural integrity. There were several other areas of concern. Be sure to check the sunroof surround. I learned that MBUSA makes zero mention of rust and corrosion on their website or in the warrenty. Personally, I'm convinced that certain 2010 Gs have a systemic rust issue if the weather conditions are not perfect.
Hi drew138,
I have a 2008 G500 with rust. Can you please elaborate your story and provide more details? I appreciate it.
The other areas are too small to really see in photos.
MBUSA has already fixed several spots on the door sills. I'm guessing that there is rust forming on the drivers side currently (all doorsill rust was on the passenger side).
Hi JD101b,
How did you get MB to fix the rust problems? Please provide details, thank you so much.
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
Hi SFinah,
You are not alone. There are many with the same problem. We should be able to get MB to correct their defective product. I bought a brand new 2008 G500 from Mercedes Benz of South Bay in Torrance California and have taken it there to get serviced from day one. They never brought to my attention that the car is rusting away in about 10 spots. Same locations as yours and the car is just getting worse. This is my wife's car so I hadn't noticed until I was dispensing gas in 2021. The car has 70k miles and its never been out of sunny California. I am trying to get together some other affected customers with MB's defective G wagons. Please provide details at: beyondmediaproductions@yahoo.com
It's not a problem with the paint. It's the improper use of sheet metal. Many of the panels were not properly galvanized prior to shaping and assembly. Unfortunately, this shoddy, cost-cutting measure was also prevalent on the W163, W202, W203, W210, and W220, from that era. There's nothing one can do short of replacing the entire body panel.
The rust will continue....either replace the panel (multiple ones), or sell the truck.
Hi motorwerksgroup
I have a 2008 G500 that I bought brand new in California. Have you seen G500 rusting away? I am trying to get MB to fix but they are refusing... It has about 10 rusting areas - same areas that everyone is mentioning.