Krown rustproofing - collateral damage (1 Viewer)

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Aug 5, 2005
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Location
Ontario, Canada
The benefits of Krown rustproofing have been discussed here. Krown-ing a vehicle does have some disadvantages as well. First, it requires drilling into doors and door jambs. Secondly, the undercarriage will attract dirt and working on the vehicle becomes less fun.

But the real problem arises when Krown comes into contact with rubber and plastic.

Our 2000 LX470 has been Krowned since 2005. Because we do not drive this vehicle a lot in the winter, we probably had Krown applied about 4 or 5 times since then - and maybe 1 or 2 more times on the undercarriage only.

Despite skipping a year (on average), rubber and plastic materials have swollen over the years. After replacing my headlight bulbs, I was unable to re-install the cover as a result of excessive swelling of the gasket. Especially softer rubbers become very gooey. Before the application of the Krown, silicone is applied to the rubbers. But this is only a temporary barrier. Krown will continue to ooze out from the weep holes and attack the rubber.

This is not a complaint. I just wanted to give a heads-up to anyone considering a Krown treatment. Going forward, I may decide to only have the undercarriage treated and not the body. Some Krown shops have offered to do this for a reduced price, but lately they seem to charge the regular amount.

Here are some samples of what to expect.

Headlights:

headlights.jpg


Door handles:

door_handle.jpg


Grill

grill.jpg
 
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I like the idea about this kind of treatment, but that kind of damage isn't ok. Any issues with rubber parts under your truck?
 
Interesting. I've Krown'd my truck the last 2 years with full treatments. When would you say the swelling became apparent?
 
I have not noticed anything like that from my Fluid Film applications. I wonder what the makeup of Krown is vs Fluid Film.
 
I have not noticed anything like that from my Fluid Film applications. I wonder what the makeup of Krown is vs Fluid Film.
I have contacted Fluid Film several times about this issue because I was paranoid of this happening to my cars.

They said they have never had an issue with any Toyota or Lexus product and the ONLY thing you should keep it away from is natural rubber weatherstripping as it may cause swelling.

All the rubber components in the engine bay and on the undercarriage is some type of synthetic rubber/plastic that is designed to withstand chemical contact, etc. so there is no worries at all about getting FF on bushings, rubber boots, seals, etc.

I have been using Fluid Film for a while and never has the slightest of issues and I lay that stuff down stupid heavy!

Krown is definitely using something else here that has caused these issues.
 
Fluid Film, Amsoil HDMP, and Boeshield T9 are my go to products for rust prevention.
 
Any issues with rubber parts under your truck?

Haven't found any issues. Maybe because the undercarriage gets washed off more? The trim around the headlights for example is the perfect spot for the material to pool. Also, the bushings are probably made to be oil-resistant.

Interesting. I've Krown'd my truck the last 2 years with full treatments. When would you say the swelling became apparent?

Hard to tell exactly. Maybe 5-6 years?

Fluid Film, Amsoil HDMP, and Boeshield T9 are my go to products for rust prevention.

Never seen Fluid Film here in Ontario (GTA). I have used T9, but it is not penetrating - I think. I do use T9 for the mowing deck of my lawn tractor, snow blower etc. How do you apply the T9? Use the spray cans? Or do you buy it in bulk?

I also noticed that some of the factory electrical tape on the wire looms seems to be loosing its stickiness and is starting to unravel. Not sure if that is related to the Krown, but the wiring under the hood is usually coated pretty good too.
 
The T9 is definitely penetrating. It cures dry and goes on clear (not amber colored like the other sprays). It does take it several days to fully dry from my experience. Just have to make sure you drive a lot to accelerate the curing process.

I definitely prefer spraying T9 out of an actual spray gun (I buy the bulk gallon size) vs their Aerosol cans as they just dump a ton of product without being able to mist it on.

It attracts ten times less dirt than fluid film.

To sum it up, I use HDMP in the high wash areas (wheel wells), Fluid Film on the undercarriage, and T9 for entire engine bay including the exterior of the motor, all brackets, door hinges, etc. works amazing. Keeps the corrosion off the aluminum of you winter drive your car in salt. I park my LX for winter so that never sees salt but my LS I sprayed every square inch of that car and it’s still completely rust free since I drove it back to IL from SoCal.
 
The T9 is definitely penetrating. It cures dry and goes on clear (not amber colored like the other sprays). It does take it several days to fully dry from my experience. Just have to make sure you drive a lot to accelerate the curing process.

I definitely prefer spraying T9 out of an actual spray gun (I buy the bulk gallon size) vs their Aerosol cans as they just dump a ton of product without being able to mist it on.

It attracts ten times less dirt than fluid film.

To sum it up, I use HDMP in the high wash areas (wheel wells), Fluid Film on the undercarriage, and T9 for entire engine bay including the exterior of the motor, all brackets, door hinges, etc. works amazing. Keeps the corrosion off the aluminum of you winter drive your car in salt. I park my LX for winter so that never sees salt but my LS I sprayed every square inch of that car and it’s still completely rust free since I drove it back to IL from SoCal.

Is there anywhere in the engine bay where you avoid spraying T9? Or is it literally everywhere. T9 appears to also act as a lubricant

BOESHIELD T-9 Rust & Corrosion Protection/Inhibitor and Waterproof Lubrication,
 
Is there anywhere in the engine bay where you avoid spraying T9? Or is it literally everywhere. T9 appears to also act as a lubricant

BOESHIELD T-9 Rust & Corrosion Protection/Inhibitor and Waterproof Lubrication,
I spray it everywhere. I do it once a year, a few weeks before winter. After spraying, I usually let the car sit inside the shop for a day or two for the chemical to cure and become semi-dry to the touch. So far, it's been amazing. I bought my LS430 in Los Angeles with zero rust or corrosion and so far I am not seeing anything so I know the Fluid film is working underneath the car and the T9 is doing its job at keeping corrosion away in the engine bay. Get it by the gallon and shoot it with a gun, I couldn't imagine doing that job with spray cans, they're not very good and just shoot a jet stream. On initial startup you'll get a burning-off odor when the engine and exhaust warm up and you'll see a slight "smoke" if you wanna call it that, but it goes away after a few minutes so no big deal. I talked to the Boeshield guys and they said they do the exact same thing every winter season on all their vehicles in Michigan. I got the idea from them years ago. I did my friend's LS400 which he bought in AZ and it's working awesome on his car too.
 
I spray it everywhere. I do it once a year, a few weeks before winter. After spraying, I usually let the car sit inside the shop for a day or two for the chemical to cure and become semi-dry to the touch. So far, it's been amazing. I bought my LS430 in Los Angeles with zero rust or corrosion and so far I am not seeing anything so I know the Fluid film is working underneath the car and the T9 is doing its job at keeping corrosion away in the engine bay. Get it by the gallon and shoot it with a gun, I couldn't imagine doing that job with spray cans, they're not very good and just shoot a jet stream. On initial startup you'll get a burning-off odor when the engine and exhaust warm up and you'll see a slight "smoke" if you wanna call it that, but it goes away after a few minutes so no big deal. I talked to the Boeshield guys and they said they do the exact same thing every winter season on all their vehicles in Michigan. I got the idea from them years ago. I did my friend's LS400 which he bought in AZ and it's working awesome on his car too.


Good info. How many winters have you been doing this? Have you considered a more “permanent” underside rustproofing solution (Rust Paint etc).

I bought a LS and LX this summer from Georgia and VA. Very little rust and hope to keep it that way.

So you still garage the LX?
 
Yup, LX is inside all winter.

Been doing the T9 and Fluid Film for two years now on our other cars. The Fluid Film doesn’t even need to be done every year. It’s literally on there 100%. I took a long time to get in everywhere the first time I did it and the second year I topped it off “just in case”, wasn’t necessary. It eventually becomes semi hard and black looking. That stuff isn’t going anywhere when it turns like that, not even with a 2,000 psi pressure washer from a very close distance (I tried). So to me, Fluid Film is the permanent solution. T9 I will keep spraying yearly because it literally takes ten minutes with a spray gun. It’s a no brainer.
 
I bought 5 Gallons of Woolwax Black, which appears to be a product similar to FF.

I’ll order 1 gallon of T9. Does T9 leave the engine tarnished or stained?



Do you still use the HDMP in the wheels?

How come you decide to garage the LX?
 
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I bought 5 Gallons of Woolwax Black, which appears to be a product similar to FF.

I’ll order 1 gallon of T9. Does T9 leave the engine tarnished or stained?



Do you still use the HDMP in the wheels?

How come you decide to garage the LX?

I would not go by the test done in that video because he is testing all these sprays on bare metal and leaving the samples outside in the sun. I am pretty sure MOST rust inhibitors do not have any UV protection which is not a problem since they are designed to go on your undercarriage. Leaving these out in the sun will greatly skew the results. There was a more accurate test done on the Raptor Forums years ago that included rain test, salt test, etc. The best sprays in the salt test actually did pretty poorly when left out in the sun.

I have not had any issues with T9 staining anything (when left alone and not washing the engine bay). I did notice that after the winter was over, I "deep cleaned" the engine bay to rinse off any possible salt. This was done by using a pressure washer and foam cannon attachment (regular car wash shampoo in the cannon), a light agitation with various sized brushes, then rinsed off and dried. After this was done, some parts did look a bit "milky" and had a slight white residue on them. I know this is not corrosion because it was happening to the plastics also. All you do at that point if it bothers you, is just to re-spray the T9 and the engine bay looks brand new again, completely gets rid of any mild staining.

As for the HDMP, there's no need to re-apply that yearly. I put down like 2-3 good layers initially on the wheels and seeing no signs of it wearing off yet.
 
I'm another believer in Fluid Film. It just works. A billion sheeps wool oils in the outdoors cant be wrong!
 
I am thinking doing cosmoline. The thick kind which you have to heat before spraying. It is not permanent, but because of that it will work all the time. Going to do underbody and more specifically frame. Everything else seems to be holding up good anyway
 
I bought my LX in Atlanta and drove it back to Buffalo, NY where it lived for a year before coming back to NC. Sacrilege I know, taking a truck that lived its entire life in the south and driving it to NY. I did a full under body POR treatment prior to salt season in NY and it has been great! My buddy worked at a subaru dealership in Buffalo for years and said that working on a car that had fluid film, or similar product, on it was among the worst experiences due to it getting everywhere and all over you. I did a full underbody cleaning, etch, and 2 layers of POR coating and UV sealant. It's been almost 3 years and still looks great.

It is time consuming (about 6 hours not including dry time between coats) but worth it!

 
Has anyone have issues with spare tire mounted under truck after Krown spray. Mine now has several small bubbles on the sidewall that got Krown on it.

IMG_2554.jpeg
 
Has anyone have issues with spare tire mounted under truck after Krown spray. Mine now has several small bubbles on the sidewall that got Krown on it.

Never seen this, but I always removed the spare tire and kept it inside the vehicle till the dripping stopped. What you are seeing does not surprise me it if it pooled on top of the tire. I recently replaced the headlight trim shown in the first picture in post #1. The trim has rubber parts and the Krown had turned it into a chewing gum like substance. I noticed the rubber gasket material underneath the doors is also sagging. After the reading the responses in this thread I started using Fluid Film and have not looked back.
 

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