ky2auburn
Junior Member
Hi everyone,
Recently traded my '15 4Runner for a '23, and want to do some undercoating this time around to try to prevent some of the surface rust I got on the frame of the '15. I've got a case of RP-342 Cosmoline (the black color) on the way. After watching some comparisons with Fluid Film, Krown, and others, I liked the longevity of the Cosmoline, as well as the fact that it doesn't stay "wet" and attract every bit of gravel and crud off the road. I found this comparison video to be pretty thorough for anyone else researching the topic: Real World Undercoating Test: Fluid Film, NH Oil, Krown and More... - YouTube
I also found this video of a guy who used Cosmoline on a GX: UNDERCOATING USING RP342 - YouTube
Questions for those who have undercoated their 4Runner:
1) What are the vents/drains that I need to take care not to stop up?
2) Any components that are best not to coat? Did you mask off any rubber pieces? I've seen that you should try not to get any on the exhaust, as it will take a while to burn it off.
3) Coverage-wise, did you spray just the frame/chassis, or did you do the entire underside, including the floor pan, spare tire wheel, etc? Planning to remove the skid plate and spray that as well. The guy in the second video looks to have hit almost everything.
4) I am planning to order some of the clear hose attachments to attach to the spray can to run up into the frame to get some coverage in there. How much product did you spray up in there? Any key hidden frame holes I need to make sure I hit with coverage?
Any other tips I should know? Thanks in advance!
Recently traded my '15 4Runner for a '23, and want to do some undercoating this time around to try to prevent some of the surface rust I got on the frame of the '15. I've got a case of RP-342 Cosmoline (the black color) on the way. After watching some comparisons with Fluid Film, Krown, and others, I liked the longevity of the Cosmoline, as well as the fact that it doesn't stay "wet" and attract every bit of gravel and crud off the road. I found this comparison video to be pretty thorough for anyone else researching the topic: Real World Undercoating Test: Fluid Film, NH Oil, Krown and More... - YouTube
I also found this video of a guy who used Cosmoline on a GX: UNDERCOATING USING RP342 - YouTube
Questions for those who have undercoated their 4Runner:
1) What are the vents/drains that I need to take care not to stop up?
2) Any components that are best not to coat? Did you mask off any rubber pieces? I've seen that you should try not to get any on the exhaust, as it will take a while to burn it off.
3) Coverage-wise, did you spray just the frame/chassis, or did you do the entire underside, including the floor pan, spare tire wheel, etc? Planning to remove the skid plate and spray that as well. The guy in the second video looks to have hit almost everything.
4) I am planning to order some of the clear hose attachments to attach to the spray can to run up into the frame to get some coverage in there. How much product did you spray up in there? Any key hidden frame holes I need to make sure I hit with coverage?
Any other tips I should know? Thanks in advance!
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