Honda and Acura Car Forums banner

Brake Fluid Flushing Problem

3K views 7 replies 4 participants last post by  nusdogg 
#1 ·
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 dealers 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:)
 
See less See more
#3 ·
Agreed. Honestly many manufactures will recommend their own products be the only thing used. Dot4 fluid is better than dot3(kind of)however both are hygroscopic fluids and will absorb moisture out of the air. Don't try and use dot5, as its silicone based and can't be used in a dot3 system.

This is why you must flush your fluid. Even though its in a fairly well sealed syste
You need to know the specifications of both fluids to really know if it is better or not.

Stoptech has a page you should read and show to the guys at that dealership.

Check it out. http://www.stoptech.com/tech_info/wp_brakefluid_1a.shtml

This will tell you why dot3 can be better than dot4. Its a worthwhile read and you can teach those shop monkeys a thing or 2.
 
#4 ·
Thanks to both of you.

I did learn interesting things from the stoptech link.

"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."
 
#7 ·
HA! So what did they have to say after your eloquent knowledge of brake fluids was presented? I hope they changed it free of charge, and are you sure they completely purged the lines? Some places can be a bit shady from time to time. Simply because employees are.lazy and don't care about the customer, or their performance.

NUSSDOGG
Its not just boiling points , there's distinct differences in the longevity of dot3/4 fluids. Some dot3s are almost the same as dot 4 fluids as boiling points go. Read that stoptech info, its in there.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top