how to protect your rig from salt damage??

[Airman68]

Everything up here in Wisconsin is automatically rusty. My buddies 2011 silverado frame rusted to the point of replacement at 130k miles. I am a big believer in POR-15. I chip off loose rust or loose factory coating where I can and put that on the outside. Pretty tough stuff, holds up well. I was thinking of the fluid film inside the frame where I cant reach.

 

[olyelr]

If this is a photo after 8 winters, then why do the untreated bolts not rust?

Some of those pics were from this last winter, and some were from the winter before.

What do you mean untreated bolts? I spray EVERYTHING (except do my best to stay away from the exhaust and brakes). That being said, after several months most of the high spray areas get kinda worn off. So there are many areas of my undercarriage which do have typical surface rust. But as far as in the body panels (which is what i care about the most), at the time of application each year the stuff from the year before is still sopping/saturated inside.

 

[Vladimir2306]

Some of those pics were from this last winter, and some were from the winter before.

What do you mean untreated bolts? I spray EVERYTHING (except do my best to stay away from the exhaust and brakes). That being said, after several months most of the high spray areas get kinda worn off. So there are many areas of my undercarriage which do have typical surface rust. But as far as in the body panels (which is what i care about the most), at the time of application each year the stuff from the year before is still sopping/saturated inside.

I see in the photo the processed parts of the frame and underbody of the car. and here are the bolts. They look like new and untreated. There's not even dirt. Well, this is strange for me.

 

[nonickatall]

If this is a photo after 8 winters, then why do the untreated bolts not rust?

Because the material is different? Frame parts are probably painted and screws are electrolytically protected.

In addition, screw heads protrude and can dry more easily.

It often rusts where sand and mud collect. Because this keeps the sheet metal or steel moist.

You can easily test this by taking an untreated sheet of metal and wetting it with a water hose. If it hangs so that it can drip and dry, you can do this again and again for decades without the sheet metal rusting through. It will form surface rust but will not rust through.

On the other hand, take a painted metal sheet and put a pile of mud on it and leave the metal sheet outside. Despite the paint, the sheet metal will have rusted through in a few years, because the mud constantly retains moisture on the surface.

That's why it's important, among other things, to clean the cars underneath regularly with a high-pressure cleaner, especially the places where mud settles in the whell housings.

And it is very important to protect the cavities, because water draws in there simply through condensation, but it has difficulty drying out and as a result cavities often remain moist for a long time. Cars usually rust in places where mud gets in, or from the inside to the outside where there are cavities.

 

[vcode]

Because the material is different? Frame parts are probably painted and screws are electrolytically protected.

In addition, screw heads protrude and can dry more easily.

It often rusts where sand and mud collect. Because this keeps the sheet metal or steel moist.

You can easily test this by taking an untreated sheet of metal and wetting it with a water hose. If it hangs so that it can drip and dry, you can do this again and again for decades without the sheet metal rusting through. It will form surface rust but will not rust through.

On the other hand, take a painted metal sheet and put a pile of mud on it and leave the metal sheet outside. Despite the paint, the sheet metal will have rusted through in a few years, because the mud constantly retains moisture on the surface.

That's why it's important, among other things, to clean the cars underneath regularly with a high-pressure cleaner, especially the places where mud settles in the whell housings.

And it is very important to protect the cavities, because water draws in there simply through condensation, but it has difficulty drying out and as a result cavities often remain moist for a long time. Cars usually rust in places where mud gets in, or from the inside to the outside where there are cavities.

Newer full size GM truck and SUV frames are wax dipped coated, not painted.

 

[vcode]

Everything up here in Wisconsin is automatically rusty. My buddies 2011 silverado frame rusted to the point of replacement at 130k miles. I am a big believer in POR-15. I chip off loose rust or loose factory coating where I can and put that on the outside. Pretty tough stuff, holds up well. I was thinking of the fluid film inside the frame where I cant reach.

Fluid Film can eat away the factory coating. I would use the factory coating, NOX-Rust X-121B or the wax based Undercoating in a Can......

 

[nonickatall]

Fluid Film can eat away the factory coating. I would use the factory coating, NOX-Rust X-121B or the wax based Undercoating in a Can......

Good information but I did my GMT 800 Escalade with the Fluid Film and I have no problems with with eat way the factoring coating...

 

[olyelr]

Newer full size GM truck and SUV frames are wax dipped coated, not painted.

Yes. And that shit SUCKS in my opinion. My wifes ‘16 denali looked like a rust bucket after its 6th northern michigan winter…the painted frame on my ram still looked new.


I stopped at the dealer checking out a new gm last year, simply ran the back side of my fingernail along the frame and it peeled that shit off down to bare metal. Pathetic.

 

[olyelr]

I see in the photo the processed parts of the frame and underbody of the car. and here are the bolts. They look like new and untreated. There's not even dirt. Well, this is strange for me.

Nope, can tell you for a fact those bolts are original to the truck. I bought it brand new. No, not much dirt…I definitely keep my stuff as clean as i can haaaaaa.

 

[olyelr]

Newer full size GM truck and SUV frames are wax dipped coated, not painted.

I have read that as well. That is why i didnt spray my wifes denali. And i will say, that thing looked like a rusty pos underneath when we got rid of it at 6 years/120k miles…my ram still had shiny black paint on the frame (bought them at the same time).