Wedge TR7 break fluid

[Michael B]

1980 TR7 what type of brake fluid should be used DOT 3 or 4 ?

 

[AngliaGT]

Use Castrol.

 

[Basil]

Michael, you posted your question in “The Pub.” I’m moving it to the Triumph forum,

 

[George_H]

I believe original was dot 3. You can use 3 or 4

 

[Sarastro]

There's little difference between the two; I think DOT4 has a slightly higher boiling point. Some brake fluids are even listed as DOT 3/4. Use whichever you can get easily.

 

[Trevor Triumph]

In my Spitfires, Herald, Austin FX4D, and Auto Union 1000 I use DOT 5. Seems to work well enough and it doesn't mess up the paint when I spill it.

 

[Hamish Racing]

But Dot 5 is silicone and should never be mixed with the other dot * even a residue when swapping over.

dot 2, 3, 4 5.1 are compatible.

I also understand that some rubber type seals are not dot 5 compatible.

 

[Deleted member 12064]

DOT is also thinner than DOT 3 or 4, which may cause leaks in your system and tends to be more difficult to bleed as it can trap more air. Its viscosity is only 900 compared to the 1800 of DOT 4 measured at the same temperature. I had tried DOT 5 but converted back to 4.