I typically had my Accord 2006 SE serviced by a local Honda dealer and my second brake fluid replacement was no exception.

However, from the invoice, I quickly realized that the technician used a Valvoline Professional Series (VPS) DOT 4 which was obviously against my Accord 06 owner manual.

"Always use Honda Heavy Duty Brake Fluid DOT 3. If it is not available, you should use only DOT 3 or DOT 4 fluid, from a sealed container, as a temporary replacement.

Using any non-Honda brake fluid can cause corrosion and decrease the life of the system. Have the brake system flushed and refilled with Honda Heavy Duty Brake Fluid DOT 3 as soon as possible. "

When I showed this paragraph to the service advisor, he first tried to convince me that the VPS DOT 4 is better than Honda HD DOT 3 and all Honda deals are using VPS DOT 4 as recommended by Honda. I asked for an official proof from Honda which he cannot provide. His service manager tried to call someone (presumable a Honda employee?) but did not succeed.

Eventually the service advisor let me make a decision whether I would like to replace the VPS DOT 4 with Honda DOT 3 free of charge. It was too late and I told him that I would let him know a few days later.

Now, my humble question is whether I should ask for a replacement from a safety point of view? BTW, The new fluid gives me a softer brake feeling than Honda Dot 3 just replaced.

Any suggestions are more than welcome

 

If it was my choice to make, I would stick with the Honda DOT 3 fluid. This is what Honda specs for the car and I think you should get it back to how the engineers that built the car have advised in the owners manual. Brakes can be expensive to completely replumb due to corrosion from using the non OEM Honda DOT 3 fluid. An ABS high pressure pump failure, a failed master cylinder or line rupture are of particular concern.You are the customer and your rights to satisfaction for safety with a softer pedal due to the different fluid used need to be a priority.

 

I've used DOT4 fluid in Hondas forever, but here's the rest of the story.

DOT4 has higher boiling points than DOT3, so in that sense DOT4 is "better".

But... DOT4 tends to pick up moisture (and become corrosive) more quickly than DOT3. So if you really do get the brake fluid refreshed every 2 or 3 years, you're fine. If you're one of those people who think brake fluid should last the life of the car, then not so good.

 

I learned an expensive lesson by using the wrong brake fluid in my Honda CB 750 front brake reservoir and caliper. It went to amber, then brown in only 1 1/2 years, ruined the pistons in the caliper, as well as seized the master cylinder bore from corrosion...BTW, the bike was stored outdoors, covered, so that only added to the problem. After buying a new set of pistons, seals and a new master cylinder, I was out almost $370...

 

Thanks to both of you! The following is what I just learnt from stoptech.com

"As a trailing note on the DOT ratings, if your car was designed for a particular type of fluid (especially prior to the development of DOT 4 fluids), you should make every attempt to stick with that fluid! For example, if your car was delivered with DOT 3 fluid, the internal components of the system (seals, brake hoses, and fittings for example) were specifically designed and tested for compatibility with DOT 3. Because DOT 4 fluids contain a different chemical composition, the system may not necessarily react in a positive fashion to the borate esters floating around in the mix.

In other cases, just the difference in viscosity of the two different fluids may cause the seals to wear at different rates. What starts as an annoying squeak might eventually become a torn seal or worse. The examples could go on and on, but the message here is this: it’s fine to upgrade from DOT 3 fluid A to DOT 3 fluid B, but you should think twice (maybe even three times) before switching from DOT 3 fluid A to DOT 4 fluid of any sort.

That said, when dealing with modern hydraulic braking systems a numerically higher DOT rating is typically considered to be compatible with a lower DOT rating (except for DOT 5, of course). Unfortunately, this same generality just isn’t true for most older hydraulic system materials."

It appears that I have to ask for a replacement of my brake fluid.

 

That is a wise decesion. Why tempt fate and have a dangerous/expensive situation that can be avoided entirely...

 

Finally the VPS DOT 4 was replaced with HG DOT 3 and the softer pedal has gone. I got my sensitive yet linear pedal back

 

Good to hear and thanks for coming back with the update.

 

DOT 4 is actually a superior fluid over DOT 3 completely.

before i go into comparisons PLEASE READ

<b>you can use DOT 4 in a DOT 3 system, BUT can not use DOT 3 in any newer systems</b>

DOT 4 has a higher boiling point, it actually resists moisture more than DOT 3(less hygroscopic)

whoever did you brake fluid bleeding before must have left air in the system, that was your soft pedal feel.

DOT 4 is the staple for newer and older vehicles alike. it is backwards compatible. but like i said, DO NOT use DOT 3 in a newer system, it will eat your seals and rubber components. it is more corrosive than DOT 4