Penetrating Fluid Jun 2018 Test: Which Brand Wins?
In our Jun 2018 test we compared 6 penetrating fluid options head to head. SeaFoam Deep Creep came out on top. See the measured results, the runner-up, the budget pick, and a link to the full test video.
SeaFoam Deep Creep
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CRC Knock'er Loose
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The quick take
The short version of why each pick lands where it does, built straight from the measured results.
“the results seem to make sense with SeaFoam Deep Creep coming out on top, followed by CRC Knock'er Loose coming in second”
The measured results
Every number below is read straight from the test. Products are listed in the order they finished.
Plexiglas 1 hour penetration
- 1SeaFoam Deep Creep
a lot of SeaFoam thoroughly penetrated, sitting in a puddle about to drip off, narrator says it really seems to work well
- 2CRC Knock'er Loose
thoroughly penetrated, went all the way down to the bottom of the bolt
- 3Brake Fluid DOT 3
penetrated and went all the way down to the bottom of the bolt
- 4WD-40 Rust Specialist
did a really good job, has gone all the way down to the bottom of the bolt
- 5BG In-Force
did not fully penetrate to the bottom of the bolt, a lot of fluid still at the top of the threads; went down the threads some but not as well as some of the other products
- 6Fluid Film
did not appear to have done much as far as penetrating, most of it remained up top
Plexiglas immediate spread
- 1SeaFoam Deep Creep
similar to CRC Knock'er Loose but did not spread away from the washer as much, more content remaining on the threads and nut
- 2CRC Knock'er Loose
mostly dried up, a little bit toward the base of the nut, started to move away from the washer slightly
- 3Brake Fluid DOT 3
remained on the washer, did not spread beyond it, did not evaporate
- 5BG In-Force
flowed all the way down the nut and into the washer, had not evaporated as quickly as some of the other products
- 6Fluid Film
very clear, much different from the rest, appeared to have slimed the entire set of nuts and bolts
- 4WD-40 Rust Specialistnot tested
How it was tested
- control group torque-to-loosen bolts (no penetrating fluid)
- Plexiglas oxidized nut/bolt visual penetration test, checked immediately after application
- same Plexiglas test rechecked after a 1 hour dwell time
- bonus test: all six fluids mixed together and applied to a separate nut/bolt, then torqued to break loose
“the results seem to make sense with SeaFoam Deep Creep coming out on top, followed by CRC Knock'er Loose coming in second”
Data notes and caveats
Sequel to a prior video (referenced but not extracted here) where acetone/ATF mix and Liquid Wrench were tested; Liquid Wrench took first place there and is mentioned only as context, not as a tested product in this video. A bonus test mixed all six products together and got 56.4 ft lbs of torque to break the bolt loose; this number applies only to the mixed blend, not to any single product, and is excluded from individual product results. Control group bolts were also torque-tested but no numeric result was given in the transcript. Beyond the explicit 1st (SeaFoam) and 2nd (CRC) place calls, the narrator does not rank the remaining four products against each other; their listed order reflects penetration-test outcome grouping (full penetration: Brake Fluid, WD-40 Rust Specialist; partial: BG In-Force; least: Fluid Film), not a stated rank.
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