I want to rust proof the chassis on my truck,But whats the best way to go about it?
I've heard undercoating is bad because it flakes off,
Paint......Water gets under it and will rust the metal out...
A new one to me is "Hot-Dip Galvanizing".
Any thoughts about that?

Lastly,whats the best method and cost effictive way to do this with good results?

This is gonna be on a TIGHT budget.....

Thanks.

(I've already put this in the general auto. forum also.)

 

If it is a bare frame, I would sandblast, but if were talking about just trying to rust proof the frame with the cab on it, I would scrape as much crud off as I could with a putty knife, then wire brush the frame. Follow that with a good heavy duty degreaser, then wash it down with a good pressure washer cleaning. Since, apparently your frame is rusty, I would treat it with "metal ready" or another metal treatment like "oshpo", then brush on some "zero rust" paint.

 

How bout POR-15?
http://www.por15.com/

 

Although I did recommend zero rust, my frame was actually painted with POR-15. I am not dissatisfied with the Por products, only saying that the zero-rust did a comparable job, was about half the price and didn't pose as many health concerns. Doing it over, I would use Zero-Rust.

 

if it is a bare frame i would have it sandblasted and powder coated

 

Powder coating such a large object isnt really budget minded. Ive used POR 15 and havent been happy with the results. Ive had issues with solvent popping, thinned or brushed on. I have started using Eastwoords version (I bought a pint and ive used less than half and half the frame is done) It doesnt require the prep that POR 15 does. Pretty much a Wire brush (by hand) to get the loose off, then a good cleaning to get the dust and dirt off, then its just a matter of brushing, rolling, or spraying on the product.

I havent used Zero Rust, Ill have to check into that for my next project

 

its really not that bad, roughly $500, as the saying goes, you get what u pay for

they even have a galvanizing powder coat, i had that applied to my rotors before the powder coat, believe me, if your putting money into your truck it is worth the investment

 

my truck had a lot of rust and i wanted to slow down the rust problem for cheap. i took a grinder to it and got as much off as possible. then i used rustoleum no rust primer and paint...for a $20 job, what do you think? do i need to step it up a bit?

 

I've heard good things about eastwoods rust converter.

 

Wow 85,that looks CLEAN.

Thanks guys,keep 'em comin'. I want to get as much personal experience from yall so I can get a good idea of what to expect out of what I do. I found a way to get under the cab without taking it off completly.

Unbolt it from the chassis,then take a block of wood and put it between the cab and floor jack,and jack it up very slowly and carefully,clean the frame,coat it and then lower the cab back down.

What do ya'll think?

POR-15,Zero-Rust,and a Rust "converter" is looking like my options. With winter coming up and expenses on my camry,Looks like the truck will have to be moved back untill spring. It amazes me that by the wheels the factory coating is still there whare as farther away its less visable if even there. I just wonder how much more weaker the truck has gotten since she was new.

Thanks guys.

 

thank you

and the method u described is more or less how i do frame offs on cars, i slide a 4x4 between the body and frame and use jacks to raise the body

good luck with your project

 

4.9L - if you want to go ultra cheap, a $10 bottle of "ospho" from your local Ace Hardware (or equivilent) will do your frame just nicely. It was enough to coat my crewcab frame twice...

The only rust you really have to remove is the flaky loose stuff. Surface rust you can leave. Which means a metal paint scraper, a screwdriver for poking, and a wirewheel can do the job good enough for ospho.

I sandblasted my frame, must because I had the truck apart enough that I could get the sand to hit everywhere...

Before and after pictures.

First: frame after the bed came off. Surface rusted to hell.
Second: Frame after ospho applied in two coats.
Third: frame snout after taking radiator support off. Yuck,
Fourth: same frame snout after repairing broken ear, application of ospho in two coats, prime and paint with rustoleum industrial black. It's almost as smooth as glass. Ignore the bubbly looking surface, that's my camera flash exhaggerating the water droplets. It rained for two days after I painted the frame.

Tell me that's not purty!

.

.

 

Wow,Frederic. And I thought mines was bad. Looks like Ospho does a lot.Any Idea how much weaker a chassis gets as it ages?
From what I've seen,all my rust is what I guess you could call surface. Nothing flaking off when I rub against it except a fine dust but that could be dirt.
I need to drive her somewhare for a while,Last time she was drove was before rita weeks ago...I let the engine run untill it warmed up couple or 3 days ago.

Thanks guys.

 

Well, the thickness and shape of the steel frame and cross members is what gives it the strength. As pieces flake off, well, it gets weaker. So as it rusts inevitably it gets weaker.

A friend of mine learned that the hard way last summer (year and a half ago). He overloaded the bed with gravel and the frame snapped on one side and bent on the other, right where the cab meets the bed. An 8' bed of gravel in an F150 wasn't too bright to begin with, certainly not an old rusty F150. Anyway, it weakens over time, and you need to address it. I did as you can see, and it was a huge pain, but at least now whatever "weakening" that has occurred has stopped.

Though, my truck is 11 years old and has over 350K+ on it. So maybe she deserves my welding up a new c-channel frame. I did that for my old 81 crewcab... though making a new frame for a 4wd truck with four leaf springs is by far easier, than the 2wd truck I have now. It's a little complex in the front But for now, the rust has been taken care of, and she hauled 3200lbs of gravel in the bed without bending, so I'm comfortable I still have some hauling capability. Most of the time I drive unloaded, anyway, which is how I accumulated most of the mileage. Or, with something hitched rather than in the bed.

 

sorry to bump this thread but how chip resistant is that rustoleum,ive got some epoxy but its so expensive i think ill save it for my body after i seen fredericks chassis thought i might use it on mine if it wont chip easy.