Interesting video of various car undercoating tests

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My tercel:: 1985 Tercel SR5. aka Spud
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Interesting video of various car undercoating tests

Post by MrWrench » Wed Jan 15, 2020 4:48 am

Found this video of a YouTuber performing tests on common automotive undercoatings. Curious what you guys think? I personally used a costing that concrete guys spray on their panels in the winter time to prevent them from sticking. Weather or not it's efficient this year I don't know. I do think I'll be going a different route next year! I plan on doing some rust repair work to Spud this summer and I'll likely be applying Fluid film next fall.
1984 Toyota Tercel SR5 winter driver rescue
1985 Toyota Tercel SR5. Daily driver. Aka "Spud"
1986 Toyota Tercel SR5. - Recent wagon rescue/project.
* ISO - any 4wd manual transmissions *

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Re: Interesting video of various car undercoating tests

Post by keith » Wed Jan 15, 2020 12:17 pm

Undercoating usually turns out to be counter-productive. It traps dirt and moisture, can block drain holes if not applied correctly, and contribute to more rust that you would have if you just leave it alone and clean the rockers and underside of the fenders periodically.

Even if you don't block the drain holes, you can get undercoating into the drain holes enough to form a lip on the top of the hole, trapping water and salt inside the panels you are trying to protect.

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