Noxudol - pros and cons?

Noxudol is supposed to last longer than other oil sprays like Krown, but it does cost more. It should be better than Woolwax.

It is not the old-school rubberized tar undercoat you don't like.

Any Toyota dealer should be able to do the Noxudol treatment, so if you don't like that dealer, you can use another. There are also other shops that do it listed on Noxudol's site. If you prefer DIY, Noxudol sells their products directly on Amazon (Noxudol is listed as the seller).

I dont know how wet the Noxudol stays when sprayed in cavities. @Trav do you have expertise on how hard it sets up after days/months/years?

Ive sprayed some cosmoline types of material in doors, tried heavy and light, and it all will set up hard, and can have cracks that would invite water. While I can appreciate the staying power of something like Cosmoline when sprayed on a few mils thick on exposed surfaces, it doesnt seem ideal to build. I had to top it with woolwax so that I was sure that there was not a place for water to sit and stand. The woolwax when not exposed to water and spray has excellent staying power and doesnt evaporate or disappear. Ive had it on some bolts on my Accord for many years in the door jambs, and it still is there.
 
I dont know how wet the Noxudol stays when sprayed in cavities. @Trav do you have expertise on how hard it sets up after days/months/years?

Ive sprayed some cosmoline types of material in doors, tried heavy and light, and it all will set up hard, and can have cracks that would invite water. While I can appreciate the staying power of something like Cosmoline when sprayed on a few mils thick on exposed surfaces, it doesnt seem ideal to build. I had to top it with woolwax so that I was sure that there was not a place for water to sit and stand. The woolwax when not exposed to water and spray has excellent staying power and doesnt evaporate or disappear. Ive had it on some bolts on my Accord for many years in the door jambs, and it still is there.

I've been using Noxudol for 4 years now. I have the luxury of a well equipped shop, a few cavity guns and quite a few wands/nozzles etc. for application. We live in Northern Ontario where salt and sand is a daily occurrence in winter with temps hitting -35C. Rust is a big deal here.

You can read a rather exhaustive discussion at the samba I fired up a few yrs ago: https://www.thesamba.com/vw/forum/archive/index.php/o-t--t-606491--.html

1. Rustcheck, Krown and Fluid Film will wash off exposed chassis parts in just a few hours of driving in heavy rain. On interior panels they fare better but really should be applied every year. This fellow’s real world tests and video are spot on :


2. Mike Sanders grease is awesome as a cavity chassis wax but needs to applied at 90-100C. I have a five gallon pail, and heat tape wrapped gun to apply it. It is a major PITA to apply and it's viscosity makes seam creep (which you want) over time unlikely unless the body gets quite hot.

3. Noxudol 700 won a three year test on body panels done by Classic Car Magazine in the UK. Google it. I did research on the product including a patent review and MSDS data. Both Noxudol 300 (black, heavier wax for exposed chassis) and Noxudol 700 (amber color, for interior or proetected panels) have active ingredients to react with and slow/stop rust. I suspect that is why Honda, Toyota and Isuzu (others?) have all specified these products for use in their recall programs. It is easy to apply and the 300/700 are solvent free.

I used the 300/700 on our 2014 Highlander during the summer of 2018 and can confirm that it has not washed off after many pressure washes..and can support the manufacturers suggestion of quick yearly touch ups vs full reapplication. I can also see surface rust under the amber 700 wax is slowly turning black, which makes sense given the active anti-rust chemicals they incorporate. Initial costs are more, but factor in the savings in subsequent years. The Highlander has required 1-2 liters of 300 over the four years for touch ups...that's it.

Honda spec’d Noxudol 300 and 700 for a frame rust recall.
https://static.nhtsa.gov/odi/rcl/2010/RCRIT-10V436-1234.pdf

Toyota also spec’d Noxudol 700 and in some cases 300 on multiple truck frame rust related recalls: https://static.nhtsa.gov/odi/rcl/2009/RCRIT-09V444-6633.pdf

I paid full pop for these products and sadly get nothing from Noxudol, however it is my current number #1 recommendation.

Finally, I did a full treatment on our 2018 LEAF, detailed here with quite a few pics: https://mynissanleaf.com/viewtopic.php?t=32082

The 300 is sprayed on exposed bits, and the 700 is used inside frame channels, doors, etc. I left the 2018 LEAF EV up on the hoist for about 4-5 days as this is what it took for the 300 to "set" up to a waxy consistency vs wet/sticky when you first apply it. You'd likely want to avoid rain for a week or so after application. I took the time to remove the 5 aero panels, fender liners, rear lights etc. to do the job right.
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The 300, right after application:

042113_1.jpg


This is some information on Noxudol from an older post on the Samba where a few of use were having the rust chat:

A bit of research on the product (Noxudol 700) yields this: http://www.google.com/patents/WO2011120646A1?cl=en

Quote:
According to one embodiment, a composition containing sulfonic acids, petroleum, overbased calcium salts in an amount of 10 to 30% by weight; fatty acids, tall-oil, polymers with isophthalic acid, pentaerythritol and tall-oil in an amount of 10 to 20% by weight; paraffin waxes and hydrocarbon waxes in an amount of less than 10%; base oil, distillates (petroleum), solvent- refined heavy paraffinic materials in an amount of 40 to 60% by weight, each percentage being based on the total weight of the wax component, may be used. This material is available as the commercial product Noxudol 700 from Auson AB, Kungsbacka, Sweden. This material is of waxy appearance and includes a liquid paraffin component.


A bit more research:

Sulphonic acids - rust cleaner
overbased calcium salts - oil additive to prevent rust
pentaerythritol - referenced in several corrosion inhibition papers.
polymers with isophthalic acid - referenced in corrosion resistance material
tall oils - used as a base for corrosion inhibitor products

It would appear that along with solvated paraffin wax, there are actually a few active ingredients that react with rust. These additives along with the persistence of the product is likely why Toyota, Isuzu and Honda have all spec'd these products for recall/warranty issues related to rust.

Sorry for the long post but I've pulled from some of my previous posts to provide a pretty good overview of the product, and why you might want to use it.
 
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@denwood Fantastic info, thank you!! Really appreciate the detailed post and links. Great job. I'm sure many others will find this useful.

Luckily it appears the dealer did a good job applying the Noxudol on my new Tacoma, at least the areas I can see. I hope it will hold up to New England weather for a long time. I'll probably bring it back for touch-up after a year or two.
I'm feeling pretty good about this stuff now, and might have it done to our other daily driver too.
 
I dont know how wet the Noxudol stays when sprayed in cavities. @Trav do you have expertise on how hard it sets up after days/months/years?

Ive sprayed some cosmoline types of material in doors, tried heavy and light, and it all will set up hard, and can have cracks that would invite water. While I can appreciate the staying power of something like Cosmoline when sprayed on a few mils thick on exposed surfaces, it doesnt seem ideal to build. I had to top it with woolwax so that I was sure that there was not a place for water to sit and stand. The woolwax when not exposed to water and spray has excellent staying power and doesnt evaporate or disappear. Ive had it on some bolts on my Accord for many years in the door jambs, and it still is there.
As others have posted it is AFAIK the only product approved by Toyota, it was also OE on SAAB and Volvo as was Cunifer brake lines.
I first used it 2008 on my Expedition, after replacing both exhaust manifolds I put polyurethane sheet frame filler pieces to cure that issue once and for all then needle scaled the whole frame before applying the Noxudol 300 and 700 in all the panels. I did it in August and after about a week it was a soft waxy film and stayed that way for years.

I sold it but saw it about 2 years ago and the frame still looked perfect, no rust had formed under the coating. These product flow into the smallest crevices but a good gun with a wand setup is helpful unless you want to go with the spay can wand route which is okay but wasteful.
I was using a commercial aircraft wheel well corrosion inhibitor prior to this, it worked very well but the cost got prohibitive.
Now I do every car with Noxudol and it pays, rust is not the huge issue was was before.
 
@Trav what source do you use for sprayable noxudol 300/700? Out of stock on the noxudol website. Not interested in aerosol.
 
@Trav what source do you use for sprayable noxudol 300/700? Out of stock on the noxudol website. Not interested in aerosol.
The one litre cans : https://www.noxudolusa.com/product/noxudol-700-cavity-wax-1-lt/ (shows in stock)
https://www.noxudolusa.com/product/noxudol-300-undercoating-1-liter/ (out of stock).

I would call them. They used to sell on Amazon but don't anymore so have ordered product from their US store to a depot (US side) and then crossed the border to pick up. Sourcing in Canada is a challenge right now unless you have the option to ship to a US address.

I suspect the whole supply issue is affecting availability.

This is my goto cavity gun: https://www.pro-teksprayequipment.com/prod/1393/rust-proofing-gun-125-psi.html

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And the same spray head but on a different cup which I've modified with a Brisk Heat tape wrapped around to keep the contents hot. I was using this to apply the Mike Sanders Grease which needs to be applied at 120 C...that's over boiling temp. The Noxudol is much, much easier to work with :)

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The one litre cans : https://www.noxudolusa.com/product/noxudol-700-cavity-wax-1-lt/ (shows in stock)
https://www.noxudolusa.com/product/noxudol-300-undercoating-1-liter/ (out of stock).

I would call them. They used to sell on Amazon but don't anymore so have ordered product from their US store to a depot (US side) and then crossed the border to pick up. Sourcing in Canada is a challenge right now unless you have the option to ship to a US address.

I suspect the whole supply issue is affecting availability.

This is my goto cavity gun:

Thanks. As far as the noxudol 700, does this cavity “wax” creep as well as penetrate? Or does it stay where it’s applied? Looking for use inside boxed frame and in hard to reach areas.

I have a spray gun from previous undercoating products.

Would the noxudol 900 be more durable than the 300 for exposed/spray areas?
 
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As others have posted it is AFAIK the only product approved by Toyota, it was also OE on SAAB and Volvo as was Cunifer brake lines.
I first used it 2008 on my Expedition, after replacing both exhaust manifolds I put polyurethane sheet frame filler pieces to cure that issue once and for all then needle scaled the whole frame before applying the Noxudol 300 and 700 in all the panels. I did it in August and after about a week it was a soft waxy film and stayed that way for years.

I sold it but saw it about 2 years ago and the frame still looked perfect, no rust had formed under the coating. These product flow into the smallest crevices but a good gun with a wand setup is helpful unless you want to go with the spay can wand route which is okay but wasteful.
I was using a commercial aircraft wheel well corrosion inhibitor prior to this, it worked very well but the cost got prohibitive.
Now I do every car with Noxudol and it pays, rust is not the huge issue was was before.

That is great information. Other than a user at thesamba (who uses Noxudol for his restorations) it's hard to find long term review comments on this product. If it retains self healing properties, never hardens, and reacts with rust, it follows that it should do a much better job preventing rust over longer terms..and your example covers about 12 years if my math is correct there.

I still check over the vehicles once a year (late summer) to touch up any of the really high exposure areas.
 
Thanks. As far as the noxudol 700, does this cavity “wax” creep as well as penetrate? Or does it stay where it’s applied? Looking for use inside boxed frame and in hard to reach areas.

I have a spray gun from previous undercoating products.

Would the noxudol 900 be more durable than the 300 for exposed/spray areas?
The 700 is lighter than the 300 and yes, it's designed specifically to have very high creep and seam penetration. On a very hot summer day, you'll see some seepage at the base of doors etc. with the 700. This is a good thing. 700 is amber coloured where the 300 is black.

Noxudol actually recommends treating the internal frame rails etc. with 700 first. Then following up with 300.

If you go with 900, I believe it is not water based, so you would use 750 as the cavity wax there. It likely sets up a bit faster, but has more VOC during cure. Just match the solvent types across the product line and you'll be fine.
 
The 700 is lighter than the 300 and yes, it's designed specifically to have very high creep and seam penetration. On a very hot summer day, you'll see some seepage at the base of doors etc. with the 700. This is a good thing. 700 is amber coloured where the 300 is black.

Noxudol actually recommends treating the internal frame rails etc. with 700 first. Then following up with 300.

If you go with 900, I believe it is not water based, so you would use 750 as the cavity wax there. It likely sets up a bit faster, but has more VOC during cure. Just match the solvent types across the product line and you'll be fine.

I was going to treat unseen areas with the 700 and was trying to decide on the outside of the chassis, etc. wasn’t sure if the 300 or the 900 offers better long term protection/durability. Descriptions are a bit vague on their website.

I currently use New Hampshire oil but looking for something much longer lasting/better protection
 
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I suspect they are quite similar, once set up in 4-5 days for abrasion. I would not try and mix 700 and 900 though during application. Use 750 (cavity) and 900 (chassis) together, or 700 (cavity) and 300 (chassis). Once the product has set up (so the water or solvent has evaporate) then mixing is probably just fine. I'm curious myself so have contacted them for more information. I'll post here once I know.

Based on the MSDS though I would not use the 900: http://www.noxudolusa.com/wp-content/uploads/2013/07/Nox-900D.pdf

The MSDS for 750 is here: http://www.noxudolusa.com/wp-content/uploads/2013/07/Nox-750.pdf
..and lists: Naphtha (petroleum), hydrotreated heavy, bensen < 0,1%:45 - 50 %, Mineral oil, corrosion inhibitors, petroleumwax, Woolfat:55 - 60 %

750 sure looks similar to WoolWax (lanolin based)..but with corrosion inhibitor additives.

MSDS for Noxudol 300: http://www.noxudolusa.com/wp-content/uploads/2013/07/Nox-300.pdf

You can see the VOC is much lower for 300, and that the 300 also lists (Section 3) a list of chemicals that are related to actively fighting corrosion. I don't see those ingredients in the 900. The 900 and 750 has also never been specified in any of the OEM factory recalls..it's always 300/700.
 
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I suspect they are quite similar, once set up in 4-5 days. I would not try and mix 700 and 900 though during application. Use 750 (cavity) and 900 (chassis) together, or 700 (cavity) and 300 (chassis). Once the product has set up (so the water or solvent has evaporate) then mixing is probably just fine. I'm curious myself so have contacted them for more information. I'll post here once I know.

Look forward to what you find out.

Maybe @Trav has some insight.
 
Thanks. As far as the noxudol 700, does this cavity “wax” creep as well as penetrate? Or does it stay where it’s applied? Looking for use inside boxed frame and in hard to reach areas.

I have a spray gun from previous undercoating products.

Would the noxudol 900 be more durable than the 300 for exposed/spray areas?
I got it from Noxudol direct and still have enough to last me a while for touch ups. It creeps in everywhere so its perfect for enclosed areas.
After about a week it will dry to a waxy film. I have not used the 900 but it looks like it may be more durable long term, my only concern was it contains bitumen and may dry too hard which may let moisture in behind it but then again my concern may be totally unfounded.
 
I guess the better question is for a vehicle with very little if any rust which product is better applicable
 
I would stick with the 300 for exposed chassis and 700 everywhere else. Doing this on a new (and very clean!!) vehicle is the best possible scenario with respect to corrosion management.

Order an extra litre or two of the 300 for annual touch-ups.
 
I would stick with the 300 for exposed chassis and 700 everywhere else. Doing this on a new (and very clean!!) vehicle is the best possible scenario with respect to corrosion management.

Order an extra litre or two of the 300 for annual touch-ups.

From what I can tell the difference is one is solvent based (900) and one is not (300). Drying times are very fast with solvent based product. The 900 also seems to contain “tar”. Looking at both they seem to both say some what soft which could make for a potential use mess as far as one working on the vehicle. My other choice was RP342 for everything exposed and either NHOU or fluid film for the inside of the chassis/unseen areas. It wouldn’t be that miserable working on a vehicle with the latter combination.
 
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Yes, the 900 and 750 are solvent based. They likely dry quicker, however the solids count (actual product) is likely less over the 300/700.

It is a bit of a mess working on the vehicle after, but the a good way to describe the product after cure is that is like a firm wax. I'd rather deal with some mess vs rust :)

I use Fluid Film on my snowblower for storage over summer, however it is gone (inside auger housing) after just one use in winter. Remember that Noxudol 700 has the corrosion reactive chemicals..FF does not.
 
Yes, the 900 and 750 are solvent based. They likely dry quicker, however the solids count (actual product) is likely less over the 300/700.

It is a bit of a mess working on the vehicle after, but the a good way to describe the product after cure is that is like a firm wax. I'd rather deal with some mess vs rust :)

I use Fluid Film on my snowblower for storage over summer, however it is gone (inside auger housing) after just one use in winter. Remember that Noxudol 700 has the corrosion reactive chemicals..FF does not.
I agree with you. My only issue is my vehicle can’t sit for 5 days without use. I suppose that’s my dilemma.

When you say “firm wax”, like, dry candle wax? Or softer?

I use the CRC marine corrosion inhibitor in my snowblower and it seems to hold up well.
 
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I think driving a day or two after is fine, but you'd want to avoid driving in the rain for a week or so after your first main application. The 300/700 stays very "wet" for 3-5 days which is not a bad thing as you're going to get very good product creep during this time. Consistency of the 300 when cured is pretty similar to paraffin wax so if you're grabbing onto a suspension component you'd have some residue on your hands. The 700 is similar.

I've applied Rust Check to our Honda chassis, and a week later driven in the rain for a few hours. Checking underneath after the car dries out, it's like the product was never there. Fluid Film and Krown, similar experiences. So my thinking on leaving the vehicle for 5 days to cure is that your investment of a few $100 will stay where you put it long term :) We tend to keep vehicles a long time...my autocross car (84 Scirocco) was on hand for 25 years, and my 90 Westfalia about 18 years. I sold them for $7K and $27K respectively so my theory on corrosion control is that it does pay off in the end.
 
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