With salty roads here soon...

I'm thinking I should start doing a frame coating every year. I don't drive it much and it stays garaged but it sounds like Toyota doesn't have the best steel...or something...

Is there a guide to where you need to spray the stuff, maybe an illustrated diagram of the most important areas? I get that you want to coat the frame rails both inside and on every side, but where else is prone to rusting from road salt? And more importantly, where do you want to avoid spraying? Some sprays are hard on rubber, for example.

I've decided I will be using "Cavity Coater" https://www.kbs-coatings.com/cavity-coater.html for this. There hasn't been any reviews that I could find for it on TW other than a few posts about someone having used it, but no details.

Finally, can I just go to a car wash and drive through and let that underbody spray thing do the cleaning or do I need to find someone with a power washer and get the wand into every nook and cranny?

 

What ever you do, don't get a one time application, as they just don't last, and condensation gets in behind it. I go to Krown rustproofing, which rustproofs the whole truck and I have them spray the shit out of my frame. It leaks like crazy for almost a week, but it's worth it in the end.

My 11 year old Honda CRV still looked great after 11 harsh winters, until it was written off in an accident. Because of this, I refused their 1st insurance offer proving it's worth, txs to the body shape.

I'm sure what ever brand of rustproofing you use, will be much better than doing nothing.

 

I second Krown, they do a great job.

 

You need to use something that gets reapplied every year. The "lifetime"stuff does not work. Hell, even spraying oil under there works better than Ziebart or those rubberized undercoating. Krown or such is much better.

 

I did my frame with WoolWax almost
3 years ago and just looked under the truck today. Besides the high wash areas, the frame looks completely coated still. I
looked inside the enclosed frame areas with a light and it looked like I just sprayed it. To your question, any area that is enclosed needs sprayed in my opinion. Those front sections being the real areas of concern. Michigan winters aren’t the worst out there, but we LOVE to salt our roads. It’s worth getting it done for sure. Oh, you can spray most lanolin products like WoolWax on rubber car parts, but stay way from door seals and those little rubbery pieces between the cab and bed.

 

Fluid Film is what you seek.

 

Just like a paint job, the better your prep work the better the finished product. Get everything clean and dry as possible and go to town spraying. You can coat just about everything underneath except the exhaust and brake parts.

Pay special attention to any box sections or hidden areas of the frame and don't forget to do the inside of the rocker panels. Pull the spare tire down too.

There is no need to coat the engine, transmission or transfer case and don't coat the drive shaft as you might upset the balance.

Oil products like Crown need to be reapplied every year, waxy products like Cosmoline endure quite well. After an initial application you will need to inspect and touch up every year but will find the product to be quite hard wearing overall.

What ever product you choose well applied and maintained they all work fairly well, all have their advantages and weaknesses.

NEVER use any "rubberized" product, they crack and hold water against whatever they are sprayed on, you won't know there is a problem until a big sheet blows off revealing the damage it was hiding.


Cosmoline is my favorite.

https://www.cosmolinedirect.com/cosmoline-rp-342-heavy-spray-military-grade-rust-preventive/

 

Great advice here.

I would suggest going with a known coating. Krown, cosmoline, fluid film, and woolwax all are proven high quality coatings. Each is great and no wrong choice with any just find which you prefer.

Coat everything metal except the exhaust and brakes.

The car wash depends on the coating. With fluid film or woolwax the carwash will further wash off some of the coating. It's recommended to reapply yearly anyways so probably not a big deal, but that depends on how much you drive and how bad the environment is. Other coatings, especially cosmoline, I guess are better with being washed.

If you are talking about prep then the more you put into it the better the results. Some ramps and tip one side up while doing a pay and spray is likely enough, you don't need a super pressure washer. Still, you likely need much better than just the underbody spray at the local touchless.

 

Awesome info, appreciate everyone contributing! Are there access holes to get inside the rocker panels? I saw a video where the guy said he had to drill a hole and then slap a grommet in it for access.

 

rubber plugs on bottom of rocker. pull all of them, hose in the protection of your choice in a heavy 360* pattern, making sure you are getting product to the next plug hole, and beyond. Ski

 

There's a thread on here with where to spray and plugs to remove. I did fluid film day after I got the truck few weeks ago. I'll do a once over end of Oct and hope for the best

https://www.tacomaworld.com/threads/how-to-fluid-film-your-3rd-gen.455241/

 

4 New England winters using Krown with my truck and my frame on my 18 looks awesome almost and almost new with only a few spots on the actual frame have a few small rust spots and thats it. Wicked impressed with the stuff.

 

Another Krown user here in the rust belt. I hot water pressure wash and undercoat the truck myself twice a year every year, I spray literally everything underneath, pull the plugs in the rockers and spray in there too, as well as the bottom of the doors. Hate doing it but it’s worth it. I make sure to get all the wires under there, and don’t worry about over spray either, generally let me truck sit for 5-7 days afterwords, and then clean off the exhaust with a rag.

Did it Friday, been sitting inside with the drip all weekend.

 

Yup I actually have holes in the door wells to get the rockers really well and just plug them up with tabs its corn based which means it's super hydrophobic I don't pressure wash mine as you want that layer to build and continue to create a shield layer between you and the salt and oxidization process during the spring.

 

It’s highly recommended to wash your vehicle in the winter around here, they use liquid road salt (brine) and it gets into everything, hence why I undercoat twice a year, truck goes back to squeaky clean in the spring to get the brine out of it every year, and then I apply undercoat again.

 

So I have full armor underneath and will just shove the hose above it and spray, but someone above mentioned to NOT do the drive shaft? In every video I've seen they always do everything underneath. If this is a problem you would think someone would say it in their vids but even the mechanics advertising it say to just "go to town" under there. Seems to me that a light film of water repellent wouldn't have much of an effect on a heavy spinning shaft...

 

Thats the only stuff i found to be really good here in new england. We get more salt and brine on our roads here then most states i've been in. The wet roads and slush would wash away any fluid flim i did on my older tundra. After more than 2 years rp-342 cosmoline has stayed put, and remains waxy to the touch. Just make sure you do 2 coats along whats mentioned in the above post.

 

I especially avoid all car wash's in the winter. They recycle salty water thats washed off other vehicles. Once that stuff is sprayed on your chassis its like a mild acid promoting rust. I'll use a garden hose in the winter if its really cruded up.
I had my truck ceramic coated. The dealer even told me to never wash the truck.

 

Just spray everything. Drive shaft would fling excess off and its not like there's a weight on this stuff that will screw your drive shaft up.
I krown once a year and will be doing so twice a year now, once in fall and in spring when the snow storms stop coming.

I recommend getting a spray can or two just for touch ups on the high impact areas if you offroad or have lots of rain.

 

that's why it's smart to coat it 2 months prior for it to run into the creases and to build up dust dirt and grime as a protective layer. my krown stays on all winter. i touch up near the wheel well as needed throughout.