preferred brake fluid

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needsaresto

needsaresto

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What brand are y'all using these days? Car in question is a 1970 Dodge Dart with 10" drums and 4 piston KH front brakes. I prefer silicone brake fluid to help prevent sticking.

Looking for help with picking a brand.

Thanks FABO!
 
Silicone bf is what I need then,but will it work fine in my old Darts brake system?
 
needsaresto said:
Silicone bf is what I need then,but will it work fine in my old Darts brake system?
Click to expand...

I've never seen any need for it in the automotive world. Especially in your case, because you will be putting it in your "old Darts brake system". Why you ask? Because under no circumstances can dot 5 mix with ANY other type brake fluid. Not even in the least amount. That is unless you want to replace every bit of rubber in the system. If the system has had dot 3, stick with dot 3 or you're askin for trouble. Mixing the fluids will make every rubber part swell up and soften up and be worthless.
 
I use the Dot 5 on the 69 and Dot 3 on the new cars. No problems with the silicone over the last ten years.
 
I run Dot 4 in both my darts.
 
I am somewhat concerned with the brake fluid boiling as I will be using headers. Thats why I was thinking silicone. Also because the caliper pistons wont seize with silicone. Big advantage seeing how my Dart will sit the winters out.

Seeing how the brake lines are all original ,maybe it's time to replace all of it. Hand forming brake lines aint fun with my weak hands,but a propane torch will help.
 
The silicone DOT 5 fluids are not all they are cracked up to be;

1. It is very easy to entrap air in the fluid when pouring it making it very tough to impossible to bleed it all out. This results in a spongy pedal.
2. Water will not mix with it so any mositure present in the system seperates out and can boil when the brakes get hot resulting in loss of braking power. Also, the seperated water can cause corrosion to happen faster than in the gycol based fluids. Pistons can actually seeze up quicker than with gycol based fluids when the corrosion occurs in the caliper.
3. Even though it has a higher boiling point it becomes compressible at a temperature lower than DOT 3's boiling point resulting in spongy brakes when hot. Gycol type fluids don't become compressible until their boiling point.
4. Its more viscus and does not work well in ABS brake systems.

If you need the highest boling point DOT fluid then DOT 5.1 is what you want. This is still a gycol based fluid and is completely compatable with DOT 3 and 4.

Racing brake fluids can have a much higher dry (no moisture content) temperature rating but they typically have a lower wet (3% moisture absorbtion) temperature rating. This makes them generally not suitable for street car use where the fluid is not regularly changed.
 
i just put some dot 3 in mine, and its a little sticky, it might not be just the fluid as i just installed disks, but still, it takes a second to get the pedal back from the floor.
 
O.K sounds like the best solution is a dot 5.1 fluid,some new rubber brake lines,steel lines and a good flush once the whole system is rebuilt.

Is there a way to prevent the calipers from sticking or do I have to live with it? It's my only real concern with the KH brakes.
 
Been running dot 5 in my dart for years. I replaced all the caliber,wheel cylinders,rubber hoses and master cylinders at the time so I figured what the hell. Just flushed the steel lines real good.
 
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