Underbody rust inhibitor treatment recommendations.

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Suntory

Suntory

Joined
May 3, 2021
Threads
4
Messages
16
Location
Illinois USA
Just took delivery of a 21 HE and looking for the best rust inhibitor for the undercarriage. I see some people like Fluid Film, any other top contenders? Also, how much is required for a full underbody treatment?

Thank you!
 
4 can. $10 each. Then go drive down a dusty road after so dust sticks to the undercarriage, or else it washes off too easily. You need to saturate the fluidfilm with dust and dirt for it to have a lasting effect.
 
WoolWax. It's a lot thicker than fluid film and doesn't wash off as fast as fluid film. If you get the WoolWax black its very easy to see any spots you might have missed. Same as above take it down a dusty road if you can. FluidFilm is great for inside of the frame and panels. It's thinner so when you spray it tends to mist out a bit more. If you get the spray cans make sure to get the kit with the long flexible tube attachment for getting inside the frame. If you have a large compressor it's a lot cheaper to buy the gallon pails. Do not attempt to spray it with any thing less than a less 30 gallon compressor with a strong motor. The compressor won't keep up and it will literally turn a 2 hour project into a 10 hour project.

What ever you go with make sure you put down plastic under the entire vehicle. It's a mess with out it. I also wear a disposable Tyvek suit with a hood. Both are thick oil you are spraying and it likes to get on everything and spread. Plastic drop cloth, Tyvec suit, gloves, rags and that will take care of 99% of the mess.

I used FluidFilm for years but switched over to WoolWax. It lasts 3x as long and I found after the first coat it's touch ups in the areas that get washed away and I no longer have to redo the entire frame, control arms ect every year. Fluidfilm also has a bizarre barn like odor that can last for a month or more. So if you park it in a garage at home that is one thing to consider. Some folks don't mind it all and some it drives crazy.

Also after you spray the crap of the inside of the frame get a bag of plugs for the frame. Close up all the factory holes in it.

www.amazon.com/woolwax-Spray-Undercoating-Kit-Black/dp/B08LKQ43T7/ref=sr_1_14?dchild=1&keywords=woolwax&qid=1620158473&sr=8-14

www.amazon.com/Fluid-Film-Extension-Number-Service/dp/B07CJWV273/ref=pd_sbs_1?pd_rd_w=ynmyg&pf_rd_p=98101395-b70f-4a52-af63-8fac2c513e02&pf_rd_r=97R24KYEQZQD6NTV1MXF&pd_rd_r=cff1abc8-b4c5-4ebd-ada4-129db1e6dbe8&pd_rd_wg=n7Abu&pd_rd_i=B07CJWV273&psc=1

Amazon product ASIN B07QVH3PT8
 
There is no real good answer for undercoating. It comes off after awhile so plan to check on it and replace as needed. Black paint does a great job.
 
PDoyle said:
There is no real good answer for undercoating. It comes off after awhile so plan to check on it and replace as needed. Black paint does a great job.
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Every proper undercoating needs to be inspected and reapplied seasonally every year. There is no short cut around it. We used to melt wax toilet rings, used motor oil and urea. It lasted maybe 2 years? Horrible for the environment but that wasn't a thought then.

Paint is the worst. It looks the best but it needs to be 100% perfect. Any micro flaw becomes a liability. It will hold salt and water under the paint, rot the metal, and you won't even see it until it's too late. And no matter how good you are you can not prep and paint the top of any frame. How do you get to the mount area? So where the paint stops is the weak link. With major restoration work yes. Remove the body, remove the engine, pull almost everything off. Sand blast the frame to bare metal, degrease 3x, etch the frame, clean again, dip in bath, seal with Gator or something similar. Notice still no "paint".
 
I agree with the woolwax fluid film idea

there are other versions as well such as bar and chain oil and local variants and everyone has a favorite but they are all the same idea.
I started with fluid film and now use wool wax on all my trucks. I live down a dirt road so I have a nice cake of dirt wool wax protection on it.

I do it yearly but the longer you do it the less likely you will need to do much each subsequent year.
Good luck
John
 
Corrosion Free. I posted many times on that, so just search for my posts on the topic.

In short: better, longer lasting, non-stinky Fluid Film. Great for DIY.
 
Not sure where in Illinois you are, but @GoISU regularly sprays member trucks with Fluid Film in the Chicago area. PM him if interested.
 
Sandroad said:
Not sure where in Illinois you are, but @GoISU regularly sprays member trucks with Fluid Film in the Chicago area. PM him if interested.
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Good call.
From what I can tell we live fairly close by. I messaged him this afternoon. Hope to hear back soon.
Thanks!
 
Lester did that said:
Every proper undercoating needs to be inspected and reapplied seasonally every year. There is no short cut around it. We used to melt wax toilet rings, used motor oil and urea. It lasted maybe 2 years? Horrible for the environment but that wasn't a thought then.

Paint is the worst. It looks the best but it needs to be 100% perfect. Any micro flaw becomes a liability. It will hold salt and water under the paint, rot the metal, and you won't even see it until it's too late. And no matter how good you are you can not prep and paint the top of any frame. How do you get to the mount area? So where the paint stops is the weak link. With major restoration work yes. Remove the body, remove the engine, pull almost everything off. Sand blast the frame to bare metal, degrease 3x, etch the frame, clean again, dip in bath, seal with Gator or something similar. Notice still no "paint".
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The truck is brand new.
 
I had LineX do a Complete rust proofing/ frame treatment on my 21 told to not wash her or drive in downpours for a week or so to allow full curing time. It dripped wax and smelled for a week afterwards but based on other user’s experiences with them I believe it was a great investment for $400 or so


they use a wax based undercoating and a thinner wax film for inside the frame and body cavities

prior to taking it in I had already primed and painted/greased the KDSS module as others had suggested
 
Lester did that said:
Even better. Stay on top of it every year. It will not rust.

Waiting for it to rust and then doing something about it is ass back words, like the hybrid mule. If it's brand new now is the time.
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To my point. Paint it. There is no underlaying rust or chips or anything stopping the paint from adhering to the surface.
 
Suntory said:
Just took delivery of a 21 HE and looking for the best rust inhibitor for the undercarriage. I see some people like Fluid Film, any other top contenders? Also, how much is required for a full underbody treatment?

Thank you!
Click to expand...

I just finished fully treating my ‘21 with a couple of different non-toxic lanolin-based products (Blaster Surface Shield and Woolwax (traditional and HV)) and CRC’s Rust Inhibitor. I spent the better part of a year researching products, what to use where, and application tips/tricks. Tons of info is out there via forums and YouTube; it’s amazing to see how far this industry has come.

I’ll try to get some photos up during the holidays and provide my feedback. I may create a separate thread to do so.

I don’t have a lift, so it was a real chore and I’m OCD, so I took my time and used a lot of product. I thought about outsourcing this to Linex, etc. but I wanted to do the job myself to know the fender liners were removed, skids dropped, and attention was paid to every nook and cranny. All in all, probably 8-10 hours of work over a couple days and I think the final materials cost was just north of $300, but it’s done and should only be maintenance/touch-ups from here on out.

I gotta say, having this project complete brings so much peace of mind, especially with a new 200 and a virgin frame - I want to keep it that way as this Land Cruiser will be hanging around for a long time and hopefully become a heirloom vehicle in my family.
 
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yonah said:
I just finished fully treating my ‘21 with a couple of different non-toxic lanolin-based products (Blaster Surface Shield and Woolwax (traditional and HV) and CRC’s Rust Inhibitor. I spent the better part of a year researching products, what to use where, and application tips/tricks. Tons of info is out there via forums and YouTube; it’s amazing to see how far this industry has come.

I’ll try to get some photos up during the holidays and provide my feedback. I may create a separate thread to do so.

I don’t have a lift, so it was a real chore and I’m OCD, so I took my time and used a lot of product. I thought about outsourcing this to Linex, etc. but I wanted to do the job myself to know the fender liners were removed, skids dropped, and attention was paid to every nook and cranny. All in all, probably 8-10 hours of work over a couple days and I think the final materials cost was just north of $300, but it’s done and should only be maintenance/touch-ups from here on out.

I gotta say, having this project complete brings so much peace of mind, especially with a new 200 and a virgin frame - I want to keep it that way as this Land Cruiser will be hanging around for a long time and hopefully become a heirloom vehicle in my family.
Click to expand...
Did you spray inside the frame, doors and tailgate?
 
Lou Gill said:
Did you spray inside the frame, doors and tailgate?
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Yes, used a 360* nozzle to apply Blaster Surface Shield inside the frame via every single drain and threaded hole in the frame rails. Same with each crossmember, inside control arms, shock mounts, etc. I had to fab my own spray nozzle for the 360* hose applicator and it worked very well. I believe I purchased a couple Woolwax 360* applicators from Amazon and modified one for the Surface Shield cans (SS was only available in cans a few months back when I started this project - it’s a new product on the market).

Inside fenders, doors, and tailgate I used Surface Shield as well.

I applied CRC Rust Inhibitor to all of the exposed fasteners and hose clamps under the hood (via a long, skinny paint brush to eliminate and overspray). I also removed the front grill and radiator cover and painted CRC RI on the radiator/grill supports, as well as the fasteners. CRC dries into a waxy, honey colored coating that is flexible, but not wet to the touch like Woolwax or Surface Shield, so it seems to be a better fit for under hood, door jam hinges, etc. applications where you don’t want a wet surface that collects dust.

Surface Shield has a neutral/clear color similar to Woolwax clear, which I used as well. I didn’t want any black tinted coatings. The clear is really a caramel-type color and still allows some visibility of labels, tick marks on adjustment bolts, etc.

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EDIT:

This guy’s channel is excellent. He has at least a half dozen videos regarding undercoatings. The four year Fluid Film review is a great testament to the effectiveness lanolin products.


Four Year Fluid Film review:
 
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