Brake fluid

[Jack Bowser]

The information about all the fluids on the forum shows the brake fluid as HACA-19542

This must be an old Ford number. I've never heard of this and the auto supply stores have NO clue what it is.

I assume we should use DOT 3.

I just had my brake booster restored and it says Silicone fluid will void the warranty so I assume Dot 3 is the corect fluid.

Can someone confirm this?

Thanks,

[Roger Zimmermann]

Your may use DOT 3 or DOT 4. On my 2 '56 Cadillacs with the same booster, I used silicone brake fluid (DOT 5) without any problem for about 30 years.

[Jack Bowser]

When I got my booster back rebuilt it had a tag on it that said Silicone would void the warranty.

I'm going to use DOT 4 because I'm told it doesn't pick up moisture as much as DOT 3.

[Joseph Stebbins]

I'm not sure why DOT 5 would cause problems in a 1950's system. I have used it since the 80's and it has always been fine. When I tore down the brakes to my 67 convertible after 25 years of having DOT 5 fluid the rubber was still supple and the insides were clean and fresh looking. I know it causes issues with the Anti-Lock systems but have never heard anything else of issue.