1956 brake fluid DOT 3 or DOT 5

[woodeye]

I replaced the brake lines and wheel cylinders on the rear brakes. somebody previously has put in disk brakes. I'm wondering what brake fluid I should use. I want to bleed and refill the entire system

 

[sre]

I replaced the brake lines and wheel cylinders on the rear brakes. somebody previously has put in disk brakes. I'm wondering what brake fluid I should use. I want to bleed and refill the entire system

Has the brake system been totally evacuated? If so I would recommend using DOT 5 silicone brake fluid. I've used Dot 5 in antique for over 30 years. It does not draw moisture or ruin paint like DOT 3. But you can't mix DOT 5 with DOT 3 I still own a 68 Mustang F/B that I converted in 1989. Never any trouble

 

[paul5456]

If you sill have brake fluid in the master cylinder take out a small sample . If its purple, it's Dot 5. If not purple, it's probably
Dot 3.

 

[woodeye]

I was thinking I should totally evacuate the system. Is there a specific procedure to to doing this? Just open it up and let gravity do the rest? Or use a vacuum pump? Once empty does it need to be flushed?

 

[Ward 57]

I was thinking I should totally evacuate the system. Is there a specific procedure to to doing this? Just open it up and let gravity do the rest? Or use a vacuum pump? Once empty does it need to be flushed?

I think I read recently on this issue that alcohol is an effective flush when changing fluids. Time for an information search. As in the X files, the answer is out there...

 

[sre]

I think I read recently on this issue that alcohol is an effective flush when changing fluids. Time for an information search. As in the X files, the answer is out there...

Alcohol is what I used to clean the system. And yes it should be flushed clean.

 

[CSPIDY]

Alcohol may have an adverse affect on rubber parts, maybe.
That being said
I have found that brake wash does a very good job of removing oil based products without breaking them down chemically.

 

[woodeye]

Are you referring to brake cleaner in the aerosol can
Thanks jeff

 

[CSPIDY]

Are you referring to brake cleaner in the aerosol can
Thanks jeff

Yes,
but you can buy it in gal containers
Zep sells it
“Brake Wash”

https://www.amazon.com/dp/B07YQBM73F/?tag=thunderbirdforum-20