POR15 on a new car frame

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I try to wash my cars underbody as much as possible, there’s always some spots I can’t quite reach until I put it on a lift, and/or sometimes it’s just not possible to keep clean due to weather pattern.

Is there any negative effect by applying POR15 or Rustoleum to a brand new vehicle frame? Will it negatively react with the factory coating? Is it even worth applying new or wait til there is some minor surface rust?
 
If I recall, it needs rust to bond to. If you don't have rust, a rust preventative would seem like a better idea.

What kind of semi permanent rust preventatives are there?

I swear I’ll never touch rubberized undercoating anymore. Not really wanting to reapply FF or any other oils on a yearly basis. Well, I’d be willing to do it but I just couldn’t go a whole winter without rinsing the underbody and weakening the application.
 
Noxudol 700 for inside panels which is just as important, it is sold in rattle cans with a wand and Noxudol 750 or 720 for the under side and frame.
Fluid film doesnt even come close to the protection level of Noxudol. Toyota spec'd Noxudol for its new replacement frames and is OE on other manufacturers.
 
Lol trav . Why so funny ? It's not fluid film , fluid film washes off easily . Blaster Shield does not .
 
Keep in mind its much more important to protect the inside of any cavities than it is the outside. In this case a frame. A majority of serious rust comes from the inside out.
Doesn't do much good if it just rusts from the other side out. Call me a fatalist but I tend to view it as a losing battle: I use FF but it's just to slow the beast, in high hopes that the rest of the car will wear out instead by the time rust is a problem. Then if the rest of the car is worn out, who cares if it's a bit rusty too? IMO it's just too much work to keep anything nice in the rustbelt only to ruin it with winter driving.
 
Doesn't do much good if it just rusts from the other side out. Call me a fatalist but I tend to view it as a losing battle: I use FF but it's just to slow the beast, in high hopes that the rest of the car will wear out instead by the time rust is a problem. Then if the rest of the car is worn out, who cares if it's a bit rusty too? IMO it's just too much work to keep anything nice in the rustbelt only to ruin it with winter driving.
I agree with you. When approaching this type of thing living in the rust belt you really must accept all you are doing is slowing the rot. The only way to keep a car rust free is to store it in salty months.

But i also feel shooting some fluid film into a bunch of cracks and holes in the undercarriage of my car is useful. If i miss one, so what? Still better off than doing nothing.
 
I agree with you. When approaching this type of thing living in the rust belt you really must accept all you are doing is slowing the rot. The only way to keep a car rust free is to store it in salty months.

But i also feel shooting some fluid film into a bunch of cracks and holes in the undercarriage of my car is useful. If i miss one, so what? Still better off than doing nothing.
Oh I agree, I still shoot mine with FF when I can, better than nothing. I might start playing with RP342 in the future, maybe on the high wash areas.

Hint: if the engine has an oil leak, but it's not really bad... don't fix! that's free oil coating right there. My engine (and my driveway) will never rust through.
 
...Is there any negative effect by applying POR15 or Rustoleum to a brand new vehicle frame? Will it negatively react with the factory coating? Is it even worth applying new or wait til there is some minor surface rust?
Like said, POR15 would require surface prep as it will do nothing for you applied over an existing paint/coating. Rustoleum would also require prep work to be done right.

I like woolwax and fluid film, but neither are a once and done application. It needs to be re-done yearly on surfaces that are wide open. In my experience, either hangs on well inside of panels, frames, etc.

If you are starting from scratch, I'd be tempted to go the noxudal route or the PB Blaster route.
 
NO! POR15 is not good for a frame in the salt belt!!!!

Get Krown, woolwax, rustchek, newhampshire undercoat, fluid film (gallon pail, not the can)
...
 
You just need to keep it clean, relatively dry and coated. I use a combo on my Tacoma. A relatively thin lube like Corrosion-X for tight spots chased with a thicker material that dries waxy, like Amsoil HDMP. I just do this in the summer, 3-4 years now, those areas are dirty, but when I clean them off - like new frame.
 
You just need to keep it clean, relatively dry and coated. I use a combo on my Tacoma. A relatively thin lube like Corrosion-X for tight spots chased with a thicker material that dries waxy, like Amsoil HDMP. I just do this in the summer, 3-4 years now, those areas are dirty, but when I clean them off - like new frame.

That’s exactly what I’m doing besides coating. Issue is CNY weather changes on a bi-weekly basis. One day it’s 50 degrees, warm enough to crawl under and rinse. Next day it snows overnight then stays below freezing for 2 weeks so there is no way to keep it clean unless I’m rinsing daily, which does nothing because the underbody never dries off.

My Tacoma frame is pretty exposed besides the front 1/3 that’s boxed I can get to almost all of it with a hose.

I’m looking for something to coat this frame, and coat the next new car I get before it sees salt. Whatever mixture they’ve been using lately is rusting out cars faster than ever.
 
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Noxudol 700 for inside panels which is just as important, it is sold in rattle cans with a wand and Noxudol 750 or 720 for the under side and frame.
Fluid film doesnt even come close to the protection level of Noxudol. Toyota spec'd Noxudol for its new replacement frames and is OE on other manufacturers.

I can only assume Toyota doesn’t apply this to their frames/sub frames, only hidden cavities right?

If they do then it obviously doesn’t work by the looks of my ES350 and Tacoma…lol
 
POR15 is all about marketing and far less about actual good results. As others said, a oil or wax based surface protectant is far better when applied correctly and frequently.
 
What kind of semi permanent rust preventatives are there?

I swear I’ll never touch rubberized undercoating anymore. Not really wanting to reapply FF or any other oils on a yearly basis. Well, I’d be willing to do it but I just couldn’t go a whole winter without rinsing the underbody and weakening the application.
Amsoil makes a nice spray.
 
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