brake fluid

[SFSPECBIKER79]

will dot 4 also be ok to use to fill brake master cylinders on my xs yamaha . thats all i have on hand, it is recommended for my honda shadow. what is the difference between the two?

[DGXSER]

Short answer is, yes it will work. Now, here will come the storm of folks saying "OH NO, That will screw stuff up!!" I know I have done it with no ill effects. There is an article on the site somewhere by a professional with knowledge of brake fluids that states Dot 3 and Dot 4 are pretty interchangable, but do not mix Dot 5 with 3 or 4. YMMV Just my Opinion.

[J.D.]

Short answer is, yes it will work. Now, here will come the storm of folks saying "OH NO, That will screw stuff up!!" I know I have done it with no ill effects. There is an article on the site somewhere by a professional with knowledge of brake fluids that states Dot 3 and Dot 4 are pretty interchangable, but do not mix Dot 5 with 3 or 4. YMMV Just my Opinion.

DOT4 can be used with or in place of DOT3; matter of fact, says so right on the bottle/can. DOT5 cannot; not only will it not mix with 3 or 4, but it'll cause the seals and o-rings to go nuts. You have to completely flush the older fluids to convert to DOT5, and since it's highly unlikely you're gonna get it all out, this really means all new seals, o-rings, cups, hoses, etc. In other words, for all practical purposes, you'd have to replace the whole brake system.

There's several good info sites on the web. Doing a Google search for "Replacing DOT3 brake fluid with DOT5", or "brake fluid compatibility" or something similar should bring up a lot of hits.

Jim

[BigDick]

yep we beat the break fluid question to death already just follow the links and read up. Old thread unless you clean the system completely out of the 3 it lowers the effective temps etc of the dot 4 because of that doubt I took my bottle of 4 back and just used 3. I know you had the 4 already but it may be worth your time to go get the 3.

[Mighty Eleven]

Yep, I've raced motocross for twenty years and I've substitute brake fluid once and I crashed so bad "because the front brake locked up"cause I switch up fluids. That's way thay have a dot 1,dot 2,dot 3 etc.

[fredintoon]

Yep, I've raced motocross for twenty years and I've substitute brake fluid once and I crashed so bad "because the front brake locked up"cause I switch up fluids. That's way thay have a dot 1,dot 2,dot 3 etc.

Hi Bob,
while I may not be older than dirt I sure got it frightened and I never heard of DOT1 or DOT2 brake fluid. What # fluids did you swap between? DOT3 or DOT4 to DOT5 will bring you grief but not any other.