Most Popular Brake Fluid Tester Review & Comparison, Gage Analysis with No Endorsements and No Bias

[@hjacobs8972]

Pure distilled water does not conduct electricity. This is why you can have Christmas lights and extension cords out in the rain and snow with few short circuits. I decided to do a test. Sure enough I put the probes in the (100%) distilled water and it said 0% water! I then tried tap water and it was above the 4% scale max. The moisture that gets into brake fluid from the air would technically be distilled water. However all the metal ions from the lines and other contaminants would quickly make the water conduct and give a reading on the meters. So not only the amount of water but the dissolved ion concentration will affect the readings. Still it gives you an idea how old/contaminated your fluid is.

[@kellyanderson7115]

I'm using a King Bolen. What I might recommend is to look at these tools as more of a relativistic test. So I tested new brake fluid and it gave me a couple of bars (maybe about 0.5%) then I tested fluid from the wheel furthest from the master (right rear in my case) and it read 2-2.5%. This is on Ram 2500 that was flushed eight years ago. In this case the tool definitely identified that there was moisture in the fluid. I also want to mention that testing at the master cylinder does not accurately reflect the moisture level at the brake caliper/drum. There is no way that the moisture level is going to equalize through a 10-15 ft span of 3/16" brake line.

[@2whlr4life]

A through & comprehensive testing procedure. An excellent video, just what I was looking for. Also about what I expected from these units. Take them with a grain of salt and gp by the book.

[@sc225]

I just got the Kingbolen in and it read 2% as good and I test it just water. That' s sad

[@vicsponjr]

very frustrating. i had an open bottle of fluid and it tested bad so i opened another bottle that was a few years old and tested it, it also tested bad so I went to the auto parts store and bought a fresh bottle of DOT 3. I tested that before doing the fluid change and that tested at 3%! Leaves me wondering if the unopened brake fluid has a shelf life or if the testers are just junk.

[@1eyedwillie]

All these types of testers are technically garbage. They are most definitely not a reliable nor repeatable gage.

[@vicsponjr]

@@1eyedwillie yeah I figured it’s just best to change out the fluid every couple years and buy it new when ready to do it.

[@1eyedwillie]

Absolutely

[@laverne5890]

Subbed&Liked!! Thank me later -> Promo>SM!

[@1eyedwillie]

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