Krown vs Penetroil vs other competitors for rust proofing?

That's not been my experience at all. Here's one of my cars treated with RP-342 cosmoline.

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And My oil sprayed car

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Both cars were out in the pouring rain today. The cosmoline car rinsed itself clean from 12" of snow, sand, salt. The oil treated car keeps attracting more and more dirt like a sponge. So I'm not sure what's happening with his strut mount.
 
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That's not been my experience at all. Here's one of my cars treated with RP-342 cosmoline.

View attachment 38144

And My oil sprayed car

View attachment 38146

Both cars were out in the pouring rain today. The cosmoline car rinsed itself clean from 12" of snow, sand, salt. The oil treated car keeps attracting more and more dirt like a sponge. So I'm not sure what's happening with his strut mount.
That oil spray pic is pretty bad. Not my experience. Was it chainsaw oil or something?

My issue with the cosmoline type products (in my case, using Amsoil HDMP) was that moisture could still diffuse, and then rust could still form. I never saw moisture pockets underneath, but some of these products can dry out after many years.

I’ve generally avoided wax coatings in spots that I can’t see or top them up. I like oil type sprays in doors and other spots where there are seams.
 
The original owner was using NH Oil undercoating. I continued on with FF the past 2 years.

The literature and SDS of Amsoil hdmp does not reference cosmoline. So it's something else. Not the same as what I'm using which is a real cosmoline. There is no moisture issue. Nothing getting underneath. I know because you can see through it.

Here is a pic of the 06 Escalade jan 24 2016. Not good.

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Here is the Escalade Jan3 2021.

20210103_103515.jpg

Hard to believe it's the same truck. It would probably be off the road by now like most other gmt800 in my area. Still haven't done the brake lines.
 
I recently picked up a 2006 mazda 3 hatchback, i also want to add that i live in canada. We have long winters here and "The city uses several products to manage the snow and ice, including a mixture of sand and salt, gravel, and magnesium chloride."


The car is in decent shape and not as bad as the other gen 1 mazda's that were in my price range. I want to keep the car for probably 2-3 years as long as no extremely large repairs. There is some light rust on the body just in some places but I don't mind too much, seems like the paint chipped off, and some light rusting in in the wheel well areas. I am looking to get the car professionally undercoated to protect against future rust/corrosion etc and was looking for recommendations. Also for the painted area's like wheel wells and where the paint is chipping off, or where there is already rust - I was thinking of repainting those areas with some touch up paint or something to cover the rust and maybe apply some product by myself every few months in those areas? thanks!

So in the city I live in, we dont have many places to get this type of work done since we are small.
There is a place that does Penetroil undercoating for $179 for my car, it seems to be a oil dripless spray type of thing, has to be reapplied yearly. This is just the undercoat quote, I don't want to spend more then this so I prefer to just get the undercoat done and do the painted places by myself etc

Outside of my city theres probably unlimited options like fluid film, corrosion free, krown etc
I called a krown dealer and seems like they can do the undercoat for $140 ish

So my question is:

1. if you were in my position which product would you get? even if its unlisted I can do some research and see what city has it. I am looking to just slowdown future rust/corrosion etc. in my case is it worth it to get krown done ? or is penetroil good enough since its local anyways? budget is no more then $200 would prefer a cheaper product if i have to have applied yearly like in the $100 range etc

2. which product do u recommend that i buy for myself which i can spray on the painted area's/places that the undercoating doesnt cover every few months or whatever


thanks!
I have tried both ( Krown/Corrosion Free ) and both are excellent products but I think only Corrosion Free offers a warranty for undercarriage for stuff like brake lines, fuel tanks ( and that’s important ). That said, personally, I would not go to any Canadian tire store to get Corrosion Free done. All Krown dealers do a great job that I have been too.

Try and avoid car washes that wash the undercarriage once you start getting it done so it will last longer ( I gave up ever washing any of my cars in the winter ) .
 
The original owner was using NH Oil undercoating. I continued on with FF the past 2 years.

The literature and SDS of Amsoil hdmp does not reference cosmoline. So it's something else. Not the same as what I'm using which is a real cosmoline. There is no moisture issue. Nothing getting underneath. I know because you can see through it.

Here is a pic of the 06 Escalade jan 24 2016. Not good.

View attachment 39125

Here is the Escalade Jan3 2021.

View attachment 39126
Hard to believe it's the same truck. It would probably be off the road by now like most other gmt800 in my area. Still haven't done the brake lines.
Is it FF you are using? I'm confused by your reference to Amsoil hdmp and Cosmoline...?
 
I have tried both ( Krown/Corrosion Free ) and both are excellent products but I think only Corrosion Free offers a warranty for undercarriage for stuff like brake lines, fuel tanks ( and that’s important ). That said, personally, I would not go to any Canadian tire store to get Corrosion Free done. All Krown dealers do a great job that I have been too.

Try and avoid car washes that wash the undercarriage once you start getting it done so it will last longer ( I gave up ever washing any of my cars in the winter ) .
But in the winter dont you want to get the salt from the underside washed off???
 
PB blaster has a new product out that is supposed to beat fluid film.

I slways spray krown first inside all the internal cavities and also the chassis, then switch over to FF thereafter. I have a little bit of fluid film left over, and need to get thru it, then I will give woolwax a try. I hear it is a little better than fluid film without the horrific smell.
 
But in the winter dont you want to get the salt from the underside washed off???
Corrosion-free guarantee's no rust on the undercarriage ( depending on which package you choose ) whereas Krown doesn't.

IIRC, I was told to take it easy with washing the underside of the car or risk washing off the rust proofing.

I live in Canada ( Eastern Ontario but work out of Quebec ) and they use lots of salt/brine yet my cars have zero rust underneath ( 13 years old and over 320,000 miles ). I take a look underneath every time I bring it in for service.

I never wash my cars in the winter.

If I wasn't rust proofing my cars I would be washing the undercarriage on a regular basis for sure.
 
Personally I think boiled linseed oil is the way to go. An application every year or two keeps the underside of a vehicle nice. BLO takes weeks to dry but stays soft enough not to chip. It seeps into the rust and corners. It turns the rust dark. Since it dries to a dull sheen, you won't get filthy if you have to work under the car. I do spray all the fasteners I think I'll have to remove someday with Blaster Corrosion Block (Better than FF IMO) before the BLO. I think I'm going to try Flood Penetrol this year, since it's cool out, and the Penetrol is supposed to harden faster than BLO. Penetrol is supposed to have a good amount of BLO in it.
 
The original owner was using NH Oil undercoating. I continued on with FF the past 2 years.

The literature and SDS of Amsoil hdmp does not reference cosmoline. So it's something else. Not the same as what I'm using which is a real cosmoline. There is no moisture issue. Nothing getting underneath. I know because you can see through it.

Here is a pic of the 06 Escalade jan 24 2016. Not good.

View attachment 39125

Here is the Escalade Jan3 2021.

View attachment 39126
Hard to believe it's the same truck. It would probably be off the road by now like most other gmt800 in my area. Still haven't done the brake lines.
What product was used on the truck? My 13 Tahoe looks nasty underneath and I’d like to get something on the frame and body to slow the rust down.
 
My pickup gets yearly treatment of NH Coatings. One thing NH Coatings has a thick brush on product for areas subject to a lot of road wash. (They have products to spray also). I don't go through the car wash with undercarriage spray.
 
What product was used on the truck? My 13 Tahoe looks nasty underneath and I’d like to get something on the frame and body to slow the rust down.
Its RP-342 Cosmoline amber in those pictures. They now sell a black. Works great with peeling GM frame wax. If you still have a lot of GM frame wax left, choose wax/cosmoline not oil. Oil softens and dilutes wax. Will make whatever is left fall off.

If you post some pictures, I can give you a better idea of what you should use
 
Here's my 05 Liberty. 224k miles, July of 04 build date. Most of its life in Wisconsin. I paint the undercarriage annually and fill every hole with fluid film (use a 2' section of fuel line with a 360 degree tip). No rust.
IMG_3677.jpegIMG_3684.jpegIMG_3683.jpegIMG_3682.jpegIMG_3681.jpegIMG_3680.jpeg
 
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