Amsoil Heavy Duty Metal Protector

Yes, it works well for that. Just make sure the bottom is clean and dry before applying it. It should be re-done yearly or at least checked and touched up.
 
Use a purpose suited oil instead. The problem with the wax coatings is that while they "self heal", they can also create entrapments where water can sit and propagate rust. Thin film oil coatings IMO are better.
 
Originally Posted By: demarpaint
Yes, it works well for that. Just make sure the bottom is clean and dry before applying it. It should be re-done yearly or at least checked and touched up.


+1. This is what I do, and have done since my car was new and it looks brand new underneath. They use some downright nasty stuff on the roads around here.
 
Originally Posted By: blackman777
Originally Posted By: JHZR2
Thin film oil coatings IMO are better.
Can you name a brand?


Carwell, Krown, CorrosionX to name a few.

Amsoil MP (note no HD) may be less viscous and an option too.
 
Originally Posted By: REDDOG
Originally Posted By: demarpaint
Yes, it works well for that. Just make sure the bottom is clean and dry before applying it. It should be re-done yearly or at least checked and touched up.


+1. This is what I do, and have done since my car was new and it looks brand new underneath. They use some downright nasty stuff on the roads around here.


In Maine I bet they do use some nasty stuff on the roads. Any of these spray on rust preventative coatings like Fluid Film, HD Metal Protector, LPS-3, etc., are a labor of love. They must be checked and reapplied at least once a year, maybe more depending on how severe the winter is, or if the vehicle is used off road.
 
It'll potentially make it easier to remove bolts, since the threads will be protected from corrosion.

I once had a lot of time and went through a new family car and removed every bolt I could easily get to on the undercarriage and treated them with a neverseise compound. I figured a few evenings doing this will save many hours of grief when the car needs repair after a number of years. Rusted bolts are a horrible fact of life here in Michigan, and easily triples the time spent on a repair.
 
Originally Posted By: blackman777
Are there any negative effects, like water getting trapped by the "waxy" coating? Or making it more difficult to remove bolts?



I see no downside at all. Kestas nailed it.
 
Originally Posted By: blackman777
Are there any negative effects, like water getting trapped by the "waxy" coating? Or making it more difficult to remove bolts?



Water can get trapped in pockets, Ive seen it. Im not against the heavy wax products, but Id personally topcoat it with something more mobile to protect against this.
 
So instead of the Amsoil's HD waxy protectant, ye recommend one of these instead?

Carwell
Krown
Amsoil protectant (oil)
CorrosionX
Fluid Film
LPS-3
Rustoleum undercoating (what is this? paint?)
 
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I am testing some of these rust proofing products right now so I thought I would bring this topic back from the dead.
I treated the truck in my sig with CorrosionX Heavy Duty and I like it alot. It is thick and durable, dries to a waxy/slimy film and only collects a small amount of dirt which rinses out of the coating easily. The downside to it is that it is very expensive, $100+ for 1 gallon.
I then bought some Fluid Film and treated the car in my sig with that. It is a versatile product, Very affordable ($40 a gallon) and it seems to have alot of uses but I am not so sure it makes a good undercoating. It never dries, stays on as a thick oil, collects alot of dirt/junk and easily rinses off the undercarriage in the high wash areas. If you were to use fluid film anywhere in the rust belt, you would have to apply it at least twice a year to keep coverage on the undercarriage.
I plan on trying Amsoil HDMP next, it seems like a durable wax style coating which hopefully will collect less dirt and last longer than Fluid film while being less expensive than corrosion X HD. If anyone here has experience with Amsoil HDMP, please share your findings. Stay tuned for updates!
 
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Originally Posted By: AMC
I am testing some of these rust proofing products right now so I thought I would bring this topic back from the dead.
I treated the truck in my sig with CorrosionX Heavy Duty and I like it alot. It is thick and durable, dries to a waxy/slimy film and only collects a small amount of dirt which rinses out of the coating easily. The downside to it is that it is very expensive, $100+ for 1 gallon.
I then bought some Fluid Film and treated the car in my sig with that. It is a versatile product, Very affordable ($40 a gallon) and it seems to have alot of uses but I am not so sure it makes a good undercoating. It never dries, stays on as a thick oil, collects alot of dirt/junk and easily rinses off the undercarriage in the high wash areas. If you were to use fluid film anywhere in the rust belt, you would have to apply it at least twice a year to keep coverage on the undercarriage.
I plan on trying Amsoil HDMP next, it seems like a durable wax style coating which hopefully will collect less dirt and last longer than Fluid film while being less expensive than corrosion X HD. If anyone here has experience with Amsoil HDMP, please share your findings. Stay tuned for updates!



Good info, please keep us updated.

As far as the Amsoil product, I used it on my Jeep and it appears to be holding up well. It does collect dirt, as expected, but nothing crazy. I check it and touch it up at each tire rotation.
 
My only complaints/problem with the Amsoil stuff is the funky smell, and the amber-brown color it turns everything.

Other than that, it could not do it's intended job ANY better!
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Thanks for the info guys. Demar, you have some of the most helpful replies around, thanks!
I am looking forward to putting the HDMP to the test. I am not really big on amsoil but they might have a real winder with their HDMP spray. I wish it was available in non areosol bulk form though. I will probably use my dad's wrangler's as the test vehicle for it and I will post here again when I do. Stay tuned folks!
 
Use the fluid film in the interior panels like doors, rockers wheel arches, box frames.

I paint the underneath with Eastwoods Rust encapsulator, top coat with Chasis Black, and then spray Eastwood HD Rust Inhibitor(waxy film) over that.
 
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