Brake Fluid

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Sundowner

Brake Fluid

#1 Post by Sundowner »

I'm about to change the brake fluid in my Sprint.
The book says that as long as it meets or exceeds a certain rating then the fluid is OK to use.
Here, down-under, I cant find any reference to the books number as we use the Yankee DOT system. DOT3, DOT4 or DOT5 (5.1 or 5.2) which I believe is silicone based.
So what is factory correct (& what do you recommend) for the Sprint? DOT3 or DOT4?
Thanks & Cheers,
Rob
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gmsclassics
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Re: Brake Fluid

#2 Post by gmsclassics »

Hi Rob
DOT 4 is the one to use. For a number of years I've used the generic one that Repco sell without issue in road cars. If you are going to do any competition, especially in summer then you could consider something with a higher boiling point such as Motul 600. It is still DOT 4.

Check all the hoses carefully while you are at it.

Geoff
Sundowner

Re: Brake Fluid

#3 Post by Sundowner »

Thanks Geoff.
Cheers,
Rob
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Re: Brake Fluid

#4 Post by Carledo »

When the Sprint was new, DOT3 was all there was. DOT4 is now the current go-to spec for production cars. DOT5 is silicone which doesn't eat paint and is not hygroscopic, but in practical terms, needs all rubber parts changing and a thorough flush of the rest of the system to use. It also seems to perform rather indifferently when hot. I am using DOT5.1 which is a synthetic racing fluid in the Carledo and it seems to perform well - but it's a bit overkill for a street car!

Steve
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.
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soe8m
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Re: Brake Fluid

#5 Post by soe8m »

Only dot 5 is silicone based. 5.1 is synthetic but not silicone.

Jeroen
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Re: Brake Fluid

#6 Post by Carledo »

soe8m wrote:Only dot 5 is silicone based. 5.1 is synthetic but not silicone.

Jeroen
That's what I said!
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.
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soe8m
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Re: Brake Fluid

#7 Post by soe8m »

Carledo wrote:
soe8m wrote:Only dot 5 is silicone based. 5.1 is synthetic but not silicone.

Jeroen
That's what I said!
Well it's an hour later over here. :oops:

Jeroen
Classic Kabelboom Company. For all your wiring needs. http://www.classickabelboomcompany.com
Sundowner

Re: Brake Fluid

#8 Post by Sundowner »

Thanks for taking the time to answer.
Would you agree then, that considering,
1) the car is largely stock standard and used mostly quietly on club runs, I should stick with the DOT3 that I think is in the car now.
2) But there are a couple of mountains nearby with winding roads, on which I enjoy driving a little spiritedly, I should consider changing to Super DOT4.
Cheers,
Rob
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Re: Brake Fluid

#9 Post by geeksteve »

You can use DOT4 in place of DOT3 without flushing the system btw, they are compatible chemically. You can top 3 off with 4 etc.
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Re: Brake Fluid

#10 Post by Carledo »

I'm actually surprised you can still buy DOT3, it hasn't been available over here for some years. I'd go for DOT4! As Steve says, it's perfectly compatible.

Steve
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.
Sundowner

Re: Brake Fluid

#11 Post by Sundowner »

Thanks for the usual good advice Gents.

I'm installing new TRW pads and giving the whole system a good going over, but once again, the book(s) wont tell me how much of the stuff I'll need so.........How much of the DOT4 stuff will I need?

I'm not doing the job, just assisting (or getting in the way, if you like) but I'm buying in all the bits.......including a new Jag timing chain tensioner which will be installed at the same time.

Again Thanks.

Cheers,
Rob
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Re: Brake Fluid

#12 Post by Carledo »

1 litre should be plenty to change the whole contents of the brake system.

Steve
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!

Maverick Triumph, Servicing, Repairs, Electrical, Recomissioning, MOT prep, Trackerjack brake fitting service.
Apprentice served Triumph Specialist for 50 years. PM for more info or quotes.
Sundowner

Re: Brake Fluid

#13 Post by Sundowner »

Thanks Steve,
Rob
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Re: Brake Fluid

#14 Post by geeksteve »

Carledo wrote:1 litre should be plenty to change the whole contents of the brake system.

Steve
Remember to get a bit extra to spill on your shoes, engine bay, overalls and floor.

Steve
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Re: Brake Fluid

#15 Post by tony g »

lol
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