Rust protection advice needed - CRC over fluid film ?
 

Last year i undercoated my 4R with fluid film.

I used spray cans and it was really messy, the can nozzles were clogging up, etc. but i did the best i could and sprayed that stuff everywhere i could reach, including in every hole that I could see.

Now I did more research and it seems CRC 06026 Heavy Duty Corrosion Inhibitor could be a better product, at least it's a one time deal, to my understanding.

I am trying to avoid having to fluid film every year ....

So how do I spray CRC over fluid fild now ? Is it possible ? Last I checked underneath, it's all a bit oily but not too bad.

I don't have a lift and fluid film was a pain to apply, if CRC can be applied one time (2 coats and giving it 12 hours for each coat to cure) I would totally go for that.

Seattle area is not really bad for rust but I still want to overcoat my 4runner.

Any thoughts appreciated.

Just pay a shop that does Fluid Film full time to do the job right. Take down your spare and skid plates and rinse off the undercarriage a few days early so its dry when you take it there.

I have an air compressor and bought a fluid film kit that has a spray gun with different nozzles. It works great for applying it. I've been using fluid film on my 5th gen since new in lovely salty illinois and don't have any rust. I do one thick coating in the fall when I put my winter wheels on. I would put down a large tarp and put it on jackstands. I just spray over what was on there before. I have no apparent rust and it seems to work great so I'm not sure going to something "better" is worth it. The fluid film does get coated in small rocks and dirt by the spring time. Works well enough for me.

Have you looked at 3m cavity wax plus? It's used at a lot of bodyshops when they do repairs and replace panels. They also sell a wand to get inside frames as well.

Check out Project Farm on youtube...he did a test on both the crc and fluid film...
Just search project farm rust.

As I recall the crc is cosmoline(sp?) ...same stuff they put on guns for super l ong term storage.

Nothing better than a freshly waxed cavity...

Now that's funny...

Srt4runner, do you clean the surfaces before you spray ? I'm thinking soap and water ? Or you just spray a new coat on top of the old one ?

I have a thin layer of grime on my underbody and it does not go away with water only.

I have watched that, and several more.

The appeal of CRC is that you only apply it once and that's it, no need to re-apply every year - as far as I understand.

I've been just applying over everything every year. I figured having a coating of grime is better than a coating of rust. Keep in mind my 4runner is 95% on road. If I had layers of thick mud from off roading I would probably try to wash most of it off first.

I highly recommend the wand.

Did cosmoline (RP342) and am very happy with the results. Cosmoline dries, fluid film, woolwax, etc, stays wet. YMMV, of course.

Back to my original question:

- can I apply CRC over fluid film ? I have not found any instructions on what is the surface requirement for applying CRC.

i think you can apply it over fluid film but if you want best results it will probably work better on a clean surface. so really its up to you to decide how much effort you want to put into this.

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