Is there a recommended ‘undercoating’ to use on these trucks.

ultane

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When I was a kid back in the 60’s and 70’s, ‘Ziebart’ was the thing to do.. Then they lost a big lawsuit sometime along the way. Now there are waxy sprays that the end user can use under their trucks to ‘rustproof’ their rigs. Does anyone have any suggestions?
 
Toyota frames are dipped (completely submerged) in a vat for corrosion treatment. However some frames have areas where moisture gets trapped and was a huge problem for older vehicles. I have watched videos of older vehicles where rusted areas were sprayed with a wax in the cavities to try and combat the corrosion issue.
I don't see where DIY spraying of wax into the cavities would hurt anything.
 
I’ll likely be doing Krown. Not sure if they exist down in the US. It’s an oil spray.
 
Rust protection on vehicles manufactured today is so much better. I’m going without a spray.

I sprayed Krown on a 2008 Jeep Wrangler every year. It kept it rust-free, true, but over time it accumulated a layer of oily, dirty gunk which made working on it unpleasant.

I sprayed a Colorado ZR2 once and almost immediately had problems with the leaf springs. Same thing as the Jeep, the oil worked its way I to nooks and crannies like it is supposed to, but it carried with it dirt and grit. The leaf springs started to make grinding noises over every bump. Ultimately had to replace them.

Just my experience…
 
I also suggest not using anything. Modern vehicles are treated during the manufacturing process and incorrect application of anything else could trap moisture and cause the very problem you are trying to prevent.

Check your warranty for how long you are protected against rust, and if using another process violates that warranty.
 
Your factory coverage is 5 years. I’ll be using Corrosion Free products from Canada and the only product recommended by their Military. Have it on my 20 year old Lexus GX that I’m selling.
 
Why is that? Genuine question.
Some of the answers above note the concerns I and others might have. If done poorly some coatings can trap moisture causing more harm than good. Some of the legit products are labour intensive to apply correctly and need to be maintained over time. Honestly there are good products out there but my opinion is that they are not necessary or worth the cost/effort involved.

I would defer to rust belt experience on this one. But my harsh Winnipeg winter experience over several vehicles is washing regularly is enough.
 
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Some of the answers above address the concerns I and others might have. If done poorly some coatings can trap moisture causing more harm than good. Some of the legit products are labour intensive to apply correctly and need to be maintained over time. Honestly there are good products out there but my opinion is that they are not necessary or worth the cost/effort involved.

I would defer to rust belt experience on this one. But my harsh Winnipeg winter experience over several vehicles is washing regularly is enough.
Not seeing your point....... The frames are factory dipped, however there are parts of the frame that have cavities that over time will trap moisture/dirt and rust. Without any additional treatment well the rust will be what it is. Applying a wax (that hardens) into those cavities would fill any voids/crevices and prevent moisture from being retained and reacting with the metal. The wax once hard will not attract grit or grime like an oil based would etc..... Toyota used to use the hard wax process (may still do IDK)
 
Not seeing your point....... The frames are factory dipped, however there are parts of the frame that have cavities that over time will trap moisture/dirt and rust. Without any additional treatment well the rust will be what it is. Applying a wax (that hardens) into those cavities would fill any voids/crevices and prevent moisture from being retained and reacting with the metal. The wax once hard will not attract grit or grime like an oil based would etc..... Toyota used to use the hard wax process (may still do IDK)
If you watch Car Care Nut’s video around the 24:20 mark, he discusses the frame and wax Toyota is using.
 
Not seeing your point....... The frames are factory dipped, however there are parts of the frame that have cavities that over time will trap moisture/dirt and rust. Without any additional treatment well the rust will be what it is. Applying a wax (that hardens) into those cavities would fill any voids/crevices and prevent moisture from being retained and reacting with the metal. The wax once hard will not attract grit or grime like an oil based would etc..... Toyota used to use the hard wax process (may still do IDK)
My point is that water will find a way inside your frame and one of the worst things that you can do is to plug up the passages and drain holes that let it out or expose it to air to dry it out. If you apply wax yourself with great care and precision I agree that it helps. If the quickie tech at the local shop (or unskilled DIY'er) does a half assed job YMMV.
 
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The wax applied inside the frame is all well and good, but all the external surfaces will eventually rust if exposed to salty winters. There are some downsides to oil spray, but having a rust free vehicle outweighs them in my opinion.
 
Woolwax, Fluid Film, and Surface Shield are some of the most common lanolin products that you can DIY. The disadvantage besides the cost and time involved is that the coating stays somewhat wet, so it'll collect dust. And it stinks for a couple of days. The advantage is that the coating can be removed with power washing, and lanolin has a long history of effective rust prevention.
 
To each their own......... wax repels water, so there's that. Anyone that tries and seals holes with wax, well shouldn't be applying wax to start with. I do plan on applying additional cosmoline wax into the inaccessible areas of my frame. The exposed areas I'm not as concerned with as I do spray the frame when needed and will be able to treat any areas that start to show signs of rust.
 
I have used Corrosion X on my jetskis and boats for years with great results. I hadn't heard of CRC 6026 and may have to give that a try.
 
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