Uncarriage Coating

[benmarks]

I Googled this beforehand, but didn't find a good answer. Does anyone know what VW used when spraying the undercarriages of our cars? Or, can you recommend something similar? The donor floorpan for my 4Motion project is white, but my car is platinum grey. We got the rear pan sandblasted and it is now totally rust-free, but there's still a fair amount of the white original covering on the underside (especially in the side wheel wells) and there are also spots where there's just paint with no protection. Before we put everything back together, it seems like a good time to re-spray the donor pan in something grey that approximates the original coating. I wouldn't be doing the whole car because, with the exception of some of the bungs, my car is surprisingly clean on the bottom. So, I'd like something that's close to what VW used since we won't be re-coating the entire underside of my car.

 

[Nero Morg]

I always thought it was wax that was then painted the same color as the rest of the car. Could be mistaken though.

 

[snakeye]

CRC marine heavy duty corrosion inhibitor

I did a lot of research and this seems to be one of the best products you can get. It sprays on thin and creeps into everything, and once dry it becomes a film of golden waxy stuff similar to the original rustproofing. Building up a few layers should give excellent rust protection.

I'm sure wurth also has something, but it's probably much harder to come by.

 

[fatmobile]

I've always used the SP-400 CRC product.
It's something that needs applied each year.
I didn't know they had something even more corrosion resistant.

 

[KrashDH]

That rubberized undercoating is a 3M product. I asked the body shop when my rocker panels were getting repaired. He didn't tell me exactly the product name but I bet a phone call to a body shop that knows that rocker panel repair for these cars specifically would be able to tell you

 

[irvingj]

I was always under the impression that VW used a paraffin-based undercoating. When I had mine done (re-done, after some body work), I went to a place that used a European product called "Waxoyl."

 

[benmarks]

Thanks for the replies. I had also emailed one my VW gurus who's no longer active on the forums, and he sent me this info. It looks like there are two OEM products for the rocker panels (resin or water-based,) and a few products for the undercarriage. I am a bit vague on the differences between the three wax-based products.

Rocker panels: AKR311KD105 or AKR311KD110 (resin or water-based)

Volkswagen Golf Service & Repair Manual - Stone chip guard - Genuine products

www.vwgolf.org

Instructions:

Volkswagen Golf Service & Repair Manual - Stone chip guard -AKR 311 KD1 05- - Stone chip guard

www.vwgolf.org

Volkswagen Golf Service & Repair Manual - Stone chip guard -AKR 311 KD1 10 - Stone chip guard

www.vwgolf.org

Undercarriage: D314D36M2 or D314D37M2 or D314D38M2 (grey or black or light)

Volkswagen Golf Service & Repair Manual - Underbody protection - Genuine products

www.vwgolf.org

Instructions:

Volkswagen Golf Service & Repair Manual - Permanent underbody protection -D 314 D36 M2-, grey - Underbody protection

www.vwgolf.org

Volkswagen Golf Service & Repair Manual - Permanent underbody protection -D 314 D37 M2-, black - Underbody protection

www.vwgolf.org

Volkswagen Golf Service & Repair Manual - Permanent underbody protection -D 314 D38 M2-, light - Underbody protection

www.vwgolf.org

Undercarriage Wax-based: D316D38A2 or D316000A1 or D322100M2

Volkswagen Golf Service & Repair Manual - Wax-based underseal - Genuine products

www.vwgolf.org

Instructions:

Volkswagen Golf Service & Repair Manual - Wax-based underseal -D 316 D38 A2 - Wax-based underseal

www.vwgolf.org

Volkswagen Golf Service & Repair Manual - Wax-based underseal -D 316 000 A1 - Wax-based underseal

www.vwgolf.org

Volkswagen Golf Service & Repair Manual - Spray wax (spraying wax) -D 322 100 M2 - Wax-based underseal

www.vwgolf.org

He also sent me this webpage with links to a bunch of different types of OEM painting and sealing products:

Volkswagen Golf Service & Repair Manual - Genuine products - General information, paint

www.vwgolf.org

As far as my car, I am going to guess, based on the slight beige tint of my undercarriage, that my car has one of the wax-based coatings over top of a thin layer of platinum grey paint:

DSC01339.JPG

• benmarks
• Feb 20, 2022

 

[benmarks]

After looking at photos of my car, I think VW used multiple products at the same time. I think the rocker panels are the 1st product with a coat of paint on top of it (the product page says it is paintable.) Inside the wheel wells, I think they used the 2nd product. And, on the undercarriage and as an additional layer in the wheel wells, they covered those areas with the wax-based product. If I look at photos of my wheel wells, they have a rubbery grey coating that doesn't look painted but with a light beige tint on top. I might be wrong that the rocker boards use a different product than the wheel wells, though.

 

[Rrusse11]

I'm a fan of Fluid Film, a lanolin based product.

 

[vandermic07]

Woolwax works good for me. Started using it on my 01 golf about 4 yrs ago. the rust was advancing rapidly until i sprayed it. It seems to have slowed down since i applied it.

I like woolwax over fluid film because WW smells less less "farmy" to me. they are both lanolin based.

 

[oilhammer]

There are several things that got used. The stuff that seeps out the holes is a waxy stuff, and seems to be either a yellowish-white or can even be more black. Depends on what year, model, assembly plant, etc. as it seems to vary.

The bottom stuff is a sound deadening stuff, which is sprayed on at the factory via a big heated gun. It isn't something you could easily duplicate on your own. It tends to be a gray/tan color. And again, some variation depending on where it was assembled.

Then there is a seam sealer, which you can get from any auto-body store. You can get it to be used with a regular caulking gun, although they used something far more industrial in the factory, which a big hose attached to it so they needn't stop to refill them. They also have different shaped nozzles on them, usually a duckbill looking thing, to lay the seam sealer flat across the part they are applying it to.

 

[GP_RZ]

I have had good luck on my trucks with a mix on new Trans fluid mixed with melted down Toilet wax seals, sound funny but workup up in the rust belt in Ontario, HD chainsaw bar oil works great too...very sticky!

 

[snakeye]

I have had good luck on my trucks with a mix on new Trans fluid mixed with melted down Toilet wax seals, sound funny but workup up in the rust belt in Ontario, HD chainsaw bar oil works great too...very sticky!

Interesting. How do you apply the stuff?

 

[GP_RZ]

Interesting. How do you apply the stuff?

Just with a normal Schutz spray gun, its basically the same as the waxoyl.

 

[benmarks]

I posted this in another thread, but I didn't end up using any of the OEM stuff. I used a Wurth product, though I wouldn't be be surprised if the Wurth stuff is what VW uses for the rocker panels and inside the wheel wells:

DSC03105.JPG

• benmarks
• Mar 11, 2022

Stoneguard Grey | Underbody | Chemical Product | Wurth USA

Stoneguard Grey Aqua based Stoneguard for repairing and restoring the original texture in all visible and underbody area such as wheel wells, inside of door panels, fenders, underside of trunk or hood and the underbody of vehicles, front and rear valances side skirts etc. Provides increased...

www.wurthusa.com

 

[GP_RZ]

Not sure what you paid for the Wurth product, but If I was going to mimic the OE coating I would spray duragaurd rubberized coating Tinted with paint to match in multiple layers till desired!