[billyk79]

IS 21000 miles a valid brake fluid change interval. MM states it is

 

[udraft]

My understanding is DOT4 is every 2 years, DOT3 every 3 years. All cars. Nice they added it to the MM, mine just has a note in the owners manual. Too many folks, even so called mechanics, ignore it all together.

 

[Carbuff2]

DOT4 should be more resistant to moisture absorption, so it should have the same 3 year interval as DOT3.

 

[racoon]

The 2018 Owners Manual (sorry, don't have a copy of 2017) says the brake fluid is DOT 3.

Specified fluid: Honda Heavy Duty Brake Fluid DOT 3

The maintenance minder section says:

If a Maintenance Minder Indicator does not appear more than 36 months after the display for item 7 is reset, change the brake fluid every 3 years.

 

[Card1]

IS 21000 miles a valid brake fluid change interval. MM states it is

Why is brake fluid replacement required on some vehicles but not on others? I had a 2005 Toyota Sienna for 13 years, 190K miles. Replacing fluid not required, I never replaced it, never had any problems.

 

[racoon]

DOT 5 brake fluid is silicon based, while DOT 3, 4, confusingly DOT 5.1 are glycol based.
DOT 5 is not compatible with the other brake fluids, and they can not be mixed.

Unless your vehicle calls for DOT 5 brake fluid you should still change it every three years.

https://www.cars.com/articles/how-often-do-i-need-to-change-my-brake-fluid-1420680336417/

 

[Carbuff2]

3 years, 190K miles. Replacing fluid not required

IMO you were lucky. Metal brake lines can and will rust (from the inside, visual inspections won't work).

A friend had a little-used vehicle's brake lines fail when our state's safety inspectors STOMPED on the brakes to test them! Imaging if it had been an emergency stop.