Mixing Brake Fluid & ATF

[martinq]

This came up in a previous thread so I decided to look into it.

Brake fluid as penetrating oil.
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2953404

I did a quick test of adding some (10%) ATF into a small cup of DOT3 brake fluid. I stirred it up and it seemed to 'blend' so I let it stand and came back to check on it later in the day. I found a small separation layer at the top and concluded that it did not mix, the ATF came up to the surface. The next day I decided to do a more proper test with some documentation to show what I've found.

The result looks like typical reaction of oil and water which is very evident in the initial pour video. I know that brake fluid is hygroscopic and that it dissolves in water. ATF is not and does not.

I had to play around with the lighting & positioning to try and capture the effect clearly. It's obvious that something has been transferred (colour) but something else has not.


Amazing Video Action!!!
=======================
Pouring ATF into DOT3 (wait till the end!)
http://vimeo.com/62838472

Stirring (mmmm, smooth and tasty)
http://vimeo.com/62838473


Full picture album here:
http://imgur.com/a/qIEVE#0

1hr later

2hrs later

13hrs later

 

[GreeCguy]

What amazes me is in the video, the brake fluid and atf do not blend or mix at all. In the pictures, there does seem to be a fluid separation, but both remain red, (as though the brake fluid was dyed red).

Is it possible that the mixture still works as a penetrating oil, but needs to be shaken at every use so that both products work together?

 

[racin4ds]

If you want a great penetrating oil use acetone and ATF, not brake fluid. The properties of brake fluid don't suit well for a penetrant anyway...

 

[Rand]

brake fluid is bad stuff.

much better things you can use.

I just bought a can of kroil(2 for 1 sale).. 15 shipped$

is about a 5 year supply for me and its in handy aerosol cans.

my neighbor's beater had some really stuck lug nuts..
and the rim was welded to the hub with crust.

as a last resort I carefully sprayed a small amount of kroil on the 2 lugnuts that were resisting me jumping on a 25" breaker bar.

they came off really easy..

then i hit the rim at the hub with a few sprays of kroil(making sure not to hit brake parts)

it FELL off 30s later.

I couldnt get it off with a board and a sledgehammer.

I then used some brake cleaner to remove all traces of the kroil.

Kroil is like PB blaster on bath salts .. really amazing spray penetrant.

 

[MolaKule]

Quote:
I did a quick test of adding some (10%) ATF into a small cup of DOT3 brake fluid. I stirred it up and it seemed to 'blend' so I let it stand and came back to check on it later in the day. I found a small separation layer at the top and concluded that it did not mix, the ATF came up to the surface. The next day I decided to do a more proper test with some documentation to show what I've found.

The result looks like typical reaction of oil and water which is very evident in the initial pour video. I know that brake fluid is hygroscopic and that it dissolves in water. ATF is not and does not.


Try a 50/50 mix of ATF and DOT3 brake fluid, like 100mL of Dot3 and 100MmL of ATF. You said you used 10% ATF and 90% DOT3.

Unless your brake fluid absorbed some major moisture, a 50/50 mix blends just fine.

Most brake fluids are hygroscopic which is why you want to change the brake fluid every two to three years. Captured moisture reduces the boiling point of the brake fluid.

 

[martinq]

Originally Posted By: MolaKule
Try a 50/50 mix of ATF and DOT3 brake fluid, like 100mL of Dot3 and 100MmL of ATF. You said you used 10% ATF and 90% DOT3.

Look at the picture/video, it's a 50/50 mix. The DOT3 was from a fresh, sealed container.

 

[martinq]

Originally Posted By: Rand
then i hit the rim at the hub with a few sprays of kroil(making sure not to hit brake parts) it FELL off 30s later.

I couldnt get it off with a board and a sledgehammer.

Interesting, so what's in the Kroil?
http://www.kanolabs.com/MSDS2013/KroilLiquid2013.pdf

(30-50%) Severely Hydrotreated Petroleum Distillates 64742-52-5
(30-50%) Light Petroleum Distillates 64742-95-6/64742-88-7/64742-47-8
(5-15%) Proprietary Ingredients Proprietary
(1-5%) Aliphatic Alcohols 78-92-2/123-42-2
(1-5%) Glycol Ether 111-76-2

 

[martinq]

Originally Posted By: GreeCguy
What amazes me is in the video

Yeah it's, "Amazing Video Action!!!"!

Originally Posted By: GreeCguy
... the brake fluid and atf do not blend or mix at all. In the pictures, there does seem to be a fluid separation, but both remain red, (as though the brake fluid was dyed red).

Is it possible that the mixture still works as a penetrating oil, but needs to be shaken at every use so that both products work together?

There is definitely something mixing between the two fluids as can be seen from the colour but you can also see (easier to do in person) that the separation between the two is still very close to 50%. Does this mean that the DOT3 side has absorbed some of the additives (besided the dye) from the ATF? Is this new Red-DOT(tm) a super penetrating lube!?

 

[martinq]

After 24+ hrs. You can just see the 50ml line in the bubble-zone.

Bigger pic in album:
http://imgur.com/a/uDT10

 

[djb]

I would expect anything mixed with DOT3/4 brake fluid to be a horrible penetrating oil.

Brake fluid doesn't wick exceptionally well, bubbles paint, and then sucks moisture to the exposed surface. Its only saving grace is that it rinses away with enough water, but mixing it with other stuff might eliminate even that.

We have PB Blaster, K-Kroil, Liquid Wrench and a few others sitting on the shelf. None are magic. Only the can of MAPP performs miracles.