Picked up a bottle of DOT5 at the dealer, popped the cover off that says DOT 5 and inside the master cylinder is amber fluid, clean too. bled both sides, clean amber color. So, what's the advice here? Assume the lines were replaced at some point and they converted it to DOT4? Is DOT5 ever amber color? I can only find that it's purple. Do I need to flush this entire thing of DOT4 and get DOT5 in? Looking for suggestions.

 

it changes color form purple to amber after awhile.

 

How could I test? This is the color

 

take some of the amber and put it on something painted over night if the paint comes off its not dot 5

 

Most people use the hood of their car for this test right?

 

I don't have any painted surfaces to test on maybe my floor jack. I read two things any confirmation if this is a good test. One to shake with some water and let it sit to see if it separates. If it separates it's dot5. If it never separates it's dot 4. Is this a good test? Another I read that touching your finger then tongue on dot3 or 4 will be bitter and dot5 is not.

Thoughts? If this is dot5 I want to flush it today. I took the pads and calipers off cleaned and greased the bolt slider on the top and cleaned the lever area the plunger was full of dirt.

 

The water test is indeed an interesting one. DOT3, 4 and 5.1 are all hygroscopic, in other words they absorb water. You don't have to shake it, simply pouring a little in, it will either mix readily or pool. If the latter it is indeed DOT5. DOT3 will absorb (it is a long time since I actually did this) about 1/3rd its bulk in water, DOT4 a bit less.

However the amber colour is itself pretty diagnostic. I've just changed the fluid in two DOT4 bikes and the old fluid is a pale colour, by no means amber.

 

I realized I have dot4 in the cars pulled a little from the master and put a couple drops of water in. It instantly mixed and turned milky. The one from my bike keeps separating so it must be very old dot5. I didn't realize it could change colors. For fun I did the bitter test. 4 is bitter for sure and 5 is not. Guess I could have figured this one out without posting but maybe it will help someone else. Thanks guys

 

I wish you guys would learn to spell color correctly. By the way they're SNEAKERS not trainers.

 

We could be here a LONG time! There's a reason we call it English......