DOT 5.1 brake fluid instead of OEM DOT 4?

Hi! I have to do the 24.000km (~14,913mi) maintenance these days. As I read, I have to change the braking fluid, so I had checked the market and saw that 5.1 is the "newest" technology.

Is there any difference? Can I just simply deflate the used oil (DOT4) and fill the system with 5.1?
1: Deflate the used oil
2: Change brake pads
3: Refill with 5.1
Is this the correct order, isnt it?


Thanks!

New doesn't always mean better. Knowing absolutely nothing about this 5.1 stuff I'd say just stick with 4. If you are hell bent on using it make sure it's compatible with all of the materials in the brake system, and check to see if it will mix with other grades of brake fluids.

Szoki333 said:

Hi! I have to do the 24.000km (~14,913mi) maintenance these days. As I read, I have to change the braking fluid, so I had checked the market and saw that 5.1 is the "newest" technology.

Is there any difference? Can I just simply deflate the used oil (DOT4) and fill the system with 5.1?
1: Deflate the used oil
2: Change brake pads
3: Refill with 5.1
Is this the correct order, isnt it?


Thanks!

Click to expand...

I would just stick with DOT 4

You won't notice any difference between 4 and 5.1 except $$$ IMHO

Personally I replace the pads first, then the fluid.

You aren't going to hurt anything by staying with DOT 4. However, if DOT 5.1 isn't compatible with seals, hoses, etc. (think ethanol gas in older bikes), then you could have a bad situation on your hands.

Like Buckshot, I know nothing about the DOT 5.1, but DOT 4 still works and we KNOW that it works in our machines.

Use the DOT4 like Honda specified. If it ain't broke, don't fix it.

I always use what mother Honda says to use,can't go wrong that way.

DOT 4 and DOT 5.1 are both glycol based and can be mixed. Do not use DOT 3!

Dot 5.1 has a higher boiling point, but requires seals resistant to borate compounds. I'd stick with Dot 4.

Old Can Ride said:

DOT 4 and DOT 5.1 are both glycol based and can be mixed. Do not use DOT 3!

Click to expand...

DOT 3,4, 5.1 can be mixed. DOT 5 can not.
Just use 3 or 4. You will never see any advantage to using 5.1

DOT4 in theory can replace DOT3 and DOT5.1 can in theory replace DOT 3 or 4. DOT3 is glycol Ether based while DOT4 and DOT5.1 are glycol ether/borate ester based. The borate ester could cause seals to wear faster on a DOT3 system. NEVER use DOT5 in a system that has had DOT3/4/5.1 in it. 3/4/5.1 all absorb water so the water is dispersed through the whole system. DOT5 is silicone based and doesn't absorb water so any water left in the system pools and can easily freeze. I believe they called the new one 5.1 because it has the same boiling point as DOT5 which is a little higher than DOT4.

For maximum compatibility of the system I have always read that you should stick with the what came in it from the manufacturer for street use.

A little time searching on Google and all the vendors I found say that 5.1 is compatible with 4.

5.0 is not compatible with anything else.

5.1 is advertised for extreme duty such as racing.

From this brief research it appears 5.1 is OK to mix with 4, but why would one want to?

DOT 5.1 has a higher wet and dry boiling point than DOT 4. I definitely understand the desire to buy the best for your machine, I may use 5.1 myself at my first flush, I am undecided. Practically speaking however, if you have not experienced any brake fade due to the DOT 4 fluid boiling you will not notice any difference in performance.

The temperatures reached by the NC7 braking system do not require anything but DOT 4. So, better is better, but not needed.

Ok, I will stick to DOT4... Dont want to mess with 5.1