Hey there everyone hope you're all well. I was wondering if anyone has ever tried using Cosmoline RP 342 as a frame coat? I've seen some videos about people using it and getting good rust prevention. If anyone has tried it, please tell us how it went, any tips, and whether it's worth the money and effort. Thanks in advance!
Has anyone ever used Cosmoline RP 342 as a frame coating?
- Thread starter NYC4Wheeler
- Start date
I'm using it for the first time. Going hard core by washing everything underneath by hand, dropping gas tank to clean behind and coat (fixed overflow issue while at it) . Coating the inside of the frame with Eastwood internal frame coating. Removed sliders to make sure all's well there. Touching up and coating the inside of everything with RP-342. There are some places that are hard to get to so I'm using a 2 ft extension tube to coal inside areas that direct spray doesn't reach.
Please let me know how it goes. I've been curious about the product and the efficacy. Thanks!
I used it as a coating for all of my bolts, body mounts, e-brake cable bracket and adjuster, and pretty much anything I could put it on underneath that was exposed metal or a bolt that might need to come off at some point. If you are doing this indoors, definitely (definitely) use a drop cloth, disposable overalls, boot coverings, eye protection, some kind of hair covering, breathing protection, neoprene gloves, and a barrier cream for any exposed skin. This stuff is not fun to clean up. Also, if you get it on your exhaust, you will be smelling it until it burns off, and I wrapped my exhaust as well as I could in thin, flexible poster board that we had laying around, and some still managed to get around the barrier.
Edited to add: I put the Cosmoline on my exposed frame bits in January of 2020. It works very well and there is definitely no rust (I just took a look at the undercarriage). My parking brake cable bracket, which was replaced with a new one at the time, still looks completely new, if just a bit gooey from the Cosmoline.
Edited to add: I put the Cosmoline on my exposed frame bits in January of 2020. It works very well and there is definitely no rust (I just took a look at the undercarriage). My parking brake cable bracket, which was replaced with a new one at the time, still looks completely new, if just a bit gooey from the Cosmoline.
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Never used Cosmoline. I use Fluid Film. Looking around, there are people who are for or against both. I can tell you that my '05 LJ has been in Minnesota since 2012 and doesn't have so much as a rusty bolt.
I don't have any gripes about Fluid Film. It works well and the odor goes away after a few days. Whatever you use, after the first snow/salt event, get underneath to look for salt residue and spray over that area. It's been my experience, at least with Fluid Film, that it's better to coat and re-spray rather than going through the car wash repeatedly. As long as the metal is coated, the salt won't get to it and it and you won't get that chemical reaction that leads to rust.
I've also plugged the holes in the outer frame rail so that water, salt and debris don't get inside.
View attachment 207882
I don't have any gripes about Fluid Film. It works well and the odor goes away after a few days. Whatever you use, after the first snow/salt event, get underneath to look for salt residue and spray over that area. It's been my experience, at least with Fluid Film, that it's better to coat and re-spray rather than going through the car wash repeatedly. As long as the metal is coated, the salt won't get to it and it and you won't get that chemical reaction that leads to rust.
I've also plugged the holes in the outer frame rail so that water, salt and debris don't get inside.
View attachment 207882
Rubicon88
TJ Addict
I switched from Krown T-40, applied by Krown, to DIY Fluid Film for 2 of my Jeeps just to see which I prefer. FF goes on sale fairly often here in both the gallon cans and the aerosols so I stock up when I can. So far I like it. Krown T-40, which I've used for decades, is a bit more expensive, is only available from Krown (I think) and it never goes on sale. I use a rustproofing gun and a Shultz gun plus some simple nozzles I made. I recently bought an extension wand for FF aerosols and it works well. I don't know what's up with the price though as I bought mine about a month ago for less than half of what's shown below. I'm convinced I can 'fabricobble' something similar for even less.
Fluid Film 360° Extension Wand for spray cans by Fluid Film: Amazon.ca: Home & Kitchen
ejay
TJ Addict
I used the Cosmoline in a can on all my steering parts when I did the ZJ upgrade. 2 coats at install. Used FF underneath everything else. So far I've had to reapply the FF 2×. Cosmoline 0. And have not even a hint of rust. You need a bit more prep with the Cosmoline but it is supposed to stay put even under a pressure washer. Everything (hopefully) will get a nice coating of Cosmoline underneath as I get time to prep underneath.
The FF has also worked well. Just need to be sure that it doesn't get washed off.
The FF has also worked well. Just need to be sure that it doesn't get washed off.
I applied RP342 to my '18 Ram when purchased new. I went with it over FF for the durability and not having to reapply every season. I power washed the undercarriage a few weeks ago prepping for winter. The RP342 is still everywhere I applied it two years later. Overall I'm very happy with it and plan on using it on the LJ once I clean the frame up.