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What undercoat to prevent rust (from snow)?

ChillyWilly21

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Any recommendations on what to use as an undercoat to prevent rust?
What is the expected cost?
Thanks
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X35

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I wouldn’t worry about the snow. It’s the salt they use on the road to melt the snow you need to worry about. There’s several options out there, Fluid Film being one. Do a google search and you’ll get plenty of results.
 

Liquid Breakfast

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Before we moved to Florida we drove our Gladiator through 3 New England winters in Massachusetts. 80 miles from us in NH there was a place called New Hampshire Oil Undercoat that we had them spray on in the fall. Worked very well for us. I think it's available everywhere.
 

Flip

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I 2nd fluid film. Great results.
 

Blade1668

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I've read about "fluid film" nothing negative. Been told by several about thoroughly cleaning then covering with chainsaw bar oil working great. The strongest advice for that was a guy I knew years ago from NH and had several 1970s vehicles without a rust problem. I remember several companies from the 90s that did a undercoating and at 2-4 year bare metal would have rusted less, in the mid west winters. I'm having to replace floor panels in my 91 Comanche due to rust. Damn I need to wash my Wrangler down and check it again too. I do have several spots of surface rust I know about.
 

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watchluvr4ever1116

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This stuff has tested good compared to Fluid Film, although I have yet to try it myself..

B'laster Surface Shield Black Series Spray Can with Trigger, Professional Automotive Undercoating for Rust Protection and Corrosion Prevention, 17.5 oz., Pack of 6 https://a.co/d/hx7mLnZ
 

20-Willys

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I live in New England and used Fluid Film. Looks good so far. Some complained about the smell and used Wool Wax instead but I didn't have that issue. I just used the rattle cans but they have various applicators available as well.
 

LukeDagny

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I've been using fluid film on my jeep and three previous vehicles including a motorhome. It works as advertised.

I bought a gallon of it and apply using a $20 undercoating spray gun. It probably takes more time stringing my compressor hose out to my driveway than it does to actually apply.

I keep an aerosol can of fluid film on hand to touch up bare metal, scratches, or the discharge chute of my snowblower.
 

hamiamham69

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All undercoatings are not created equal. There are a number of great you tube review type videos. Some of the brands have been mentioned above. Lanolin based coatings seem to be the new best thing but petroleum based ones are used extensively as well.

In you are not doing it yourself make sure you know what you are getting for the money. At a minimum your undercarriage needs a serious power wash and dry and at the max needs the existing rust - at least the flakey stuff - to be mechanically removed and/or overcoated with various products.
 

GeorgeYJ2JL

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I've used Krown here in PA. My RAM 1500 is 9 years old and still looks great. No rust noted up till now, so I used it on the new Willys I just purchased. It costs $139 for a truck and $129 for a car/Jeep. I do it once a year and there's a warranty if there is through and through rust.

Jeep Wrangler JL What undercoat to prevent rust (from snow)? IMG_2133


Jeep Wrangler JL What undercoat to prevent rust (from snow)? IMG_4125
 
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LukeDagny

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All undercoatings are not created equal. There are a number of great you tube review type videos. Some of the brands have been mentioned above. Lanolin based coatings seem to be the new best thing but petroleum based ones are used extensively as well.

In you are not doing it yourself make sure you know what you are getting for the money. At a minimum your undercarriage needs a serious power wash and dry and at the max needs the existing rust - at least the flakey stuff - to be mechanically removed and/or overcoated with various products.
Good points. I have an undercarriage attachment for my pressure washer. Every Fall, I thoroughly clean underneath and re-apply Fluid Film. I've noticed some of the nooks and crannies don't need re-application.
 

Wkaz

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Any recommendations on what to use as an undercoat to prevent rust?
What is the expected cost?
Thanks
I buy fluid film in aerosol cans @ lowes. Give it a squirt here and there and everywhere when I do oil changes.
 

nU7OuxIx

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Another fluid film user. There's a number of products out there that I've researched and I think they work good. I just applied some to the internal frame rail on my new jeep. It's unbelievable how much FF creeps and spreads. I would say there's about a 5" diameter spread around holes. And I didn't even hit those areas...just the internal rail.

The only downside is having to reapply every year. But after a couple of years I would say it just needs some touchup.
 

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I thought our vehicles are rustproofed from factory…
 

m3reno

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I've been using Surface shield. It stays on a bit longer vs fluid film. My Ram is an 09 with almost 0 rust. My rockers rusted out as I forgot to spray inside the rockers. On the Jeep it's rust free going on 4 years.
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