Brake fluid

[corsinita]

I have a 72 Coupe and have the original brake fluid in it.   Can I add Dot 3 brake fluid to the system without hurting anything?   Joe C.

[feltonminicycle]

If it truly is the *original* fluid you should flush the system with the new fluid DOT 3, DOT 4 or DOT 5. If you are using DOT 5 you should try to pump out all the old fluid first.
Miles

[Bill]

When I converted to DOT 5 in my Vette back in 1982 I changed all the calipers, and flushed the system with denatured alcohol twice to make sure I removed all of the DOT 3 in the system.  This was the recommendation of the company that provided the stainless steel sleeved calipers.  I have been using DOT 5 in both my Vette and Honda 600's for over 30 years and only chaged it out three times.  In my opinion DOT 5 is the best bet for vehicles you are not driving often.
Bill

[Alan Stanyon]

I second what Bill says just remember dot 5 is silicone based and dot 5.1 is glycol based confusing i know!. dot 3 4 5 wont "mix" but they will happily "share" the braking  system but then you lose the advantages of silicon ie non hygroscopic (read no water no rust) 500 f boiling point and wont damage paint, again as Bill says silicon dot 5 is a fit and forget fluid or use the cheap version ie 3 4 5.1 and change every 2 years.

[Lyle Trudell]

Hi Bill, I agree, silicone DOT is the best for vintage cars! I drove my Honda this morning because the heater works almost instantly. It got down to 35 degree's this morning in Clearwater, FL. Damn global warming : )   Lyle

[Bill]

There is an article on the use of DOT5 brake fluid in the anzhona600owners files section (URL below) that reviews the use of DOT5.
https://groups.yahoo.com/neo/groups/anz ... ners/files

[Joseph Corsinita]

On Friday, February 20, 2015 12:55 AM, "Alan Stanyon alanstanyon@... [2cylinderhondas]" wrote:
I second what Bill says just remember dot 5 is silicone based and dot 5.1 is glycol based confusing i know!. dot 3 4 5 wont "mix" but they will happily "share" the braking  system but then you lose the advantages of silicon ie non hygroscopic (read no water no rust) 500 f boiling point and wont damage paint, again as Bill says silicon dot 5 is a fit and forget fluid or use the cheap version ie 3 4 5.1 and change every 2 years.