Brake fluid selection

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Habitat.pat
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Brake fluid selection

Post by Habitat.pat »

For decades I used Castrol GTLMA brake fluid, then they discontinued it. Castrol then came out with Brake Fluid DOT4 as a replacement. Great! Today I was talking to Castrol & found that due to supply problems they have discontinued Brake Fluid DOT4 & there is no direct replacement. They are recommending REACT SRF racing BRAKE FLUID, but it requires a flush.

Does anyone have a recommendation on where I should go from here? I’m in the middle of filling the brakes during my restoration, so I’m tempted to see if I can find enough Brake Fluid DOT4 then wait to see what Castrol comes up with before my next brake fluid change.

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Pat
67.5 SPL311 Stroker Restomod?
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redroadster
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Re: Brake fluid selection

Post by redroadster »

The light 311 only really needs dot 3
Dot 4 was engineered for heavy vehicles , think a 4x4 truck in Texas in July .they drive 80
New fluid is harsher on seals our dealer quit flushing brake fluid after a rash of pedals going to the floor after changing fluid
( techs can and are sued over work they do )
Last edited by redroadster on Tue Aug 23, 2022 9:00 pm, edited 1 time in total.
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redroadster
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Re: Brake fluid selection

Post by redroadster »

The light 311 only
Datsun dealer tech 76 to 87
Mitsubishi tech 9 yrs
Volvo, Kia, Toyota too
6 month - Rolls Royce
ASE MASTER TECH 96. - 11
70 SPL 86 Z31 T , Sportster
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Bwk2000
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Re: Brake fluid selection

Post by Bwk2000 »

Pat. Not sure if I understand. Are you saying Castrol DOT 4 is the only DOT 4 you can use? I would think that any manufacturer’s DOT 4 would work just as well 🤔
Kai
Halifax, N.S.
‘69 SPL311 Sports 1600

Classic Cars - Because clean fingernails, free weekends, intact knuckles and financial stability are totally overrated.
Habitat.pat
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Re: Brake fluid selection

Post by Habitat.pat »

Kai, No, I just have been using the LMA & Brake Fluid DOT4 because they have very low water absorption. There were tests done long ago that showed that GTLMA didn't absorb nearly as much water as other brands. Since most of our cars don't get driven all that much & the brake parts are not cheap, I chose to go with this line. Any DOT3 or DOT4 will work, hence my question of what brake fluid folks are using (Brake Fluid Selection wasn't the best subject, sorry.)

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Pat
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Bwk2000
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Re: Brake fluid selection

Post by Bwk2000 »

Interesting … I did not know that. Thanks for explaining it.
Kai
Halifax, N.S.
‘69 SPL311 Sports 1600

Classic Cars - Because clean fingernails, free weekends, intact knuckles and financial stability are totally overrated.