Need help Brake Fluid
- Thread starter Sgreg
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Most people use good quality DOT4 fluid, the general feeling is to avoid the silicone fluids as they tend to cause failuire of the brake light switch.
Was there a reason they specified silicone fluid?
Was there a reason they specified silicone fluid?
Does your system have glycol fluid in it now? I ask because changing to Silicone might cause other issues. IMO the system should be completely new and dry to attempt to change to Silicone.
Stainless pistons work just as well with glycol or Silicone. It's the old Girling rubber that may have a problem with Silicone.
By the way, in more than 25 years of using Silicone in a Cobra, I have replaced the brake pressure switch twice.
I would love to use DOT 5 in my car too due to it being paint safe. I thought that, as pointed out, the fluid does not do well with the Brit rubber. I am running Castrol GT/LMA.
A note from SS site: IMPORTANT: USE ONLY GIRLING (DOT 4) OR CASTROL GT LMA DOT 4 BRAKE FLUID OR GIRLING DOT 5.1 IN GIRLING HYDRAULIC SYSTEMS.
More info - Lucas GIrling DOT 5.1 (non-silicone base) is an ultra high-performance brake and clutch fluid which combines exceptionally high "wet" & "dry" boiling points.
A note from SS site: IMPORTANT: USE ONLY GIRLING (DOT 4) OR CASTROL GT LMA DOT 4 BRAKE FLUID OR GIRLING DOT 5.1 IN GIRLING HYDRAULIC SYSTEMS.
More info - Lucas GIrling DOT 5.1 (non-silicone base) is an ultra high-performance brake and clutch fluid which combines exceptionally high "wet" & "dry" boiling points.
My Tiger presently has Silicone DOT 5 that the PO installed. The silicone was used in response to the stainless sleeves when the calipers were rebuilt. I have a Lockheed booster I am converting to a Girling and that is why I asked the question. Silicone, I have heard is not a good idea with the Girling unit but seems fine with the Lockheed booster. Can the system be purged successfully of the silicone or is it a big deal to just flush the silicone with DOT 4? Based on the comments here, I will probably go with
the DOT 4 recommended for the Girling.
the DOT 4 recommended for the Girling.
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Once more and again
From the experienced old guy: I have had, in the past, issues with Girling seals turning into some form of soft flubber when "silly clone" is added. But not lately! The issue is the chemistry being non-compatible; make sure all the old stuff is gone, gone, flushed. My feeling is also that the newer seals are a bit harder compound and although they drag a bit in the control valve function, manage to swim well in the fake stuff. Still, after having done more than 300 of the little Girlings in 4 decades, it's a mystery when they work!! keepin' em' runnin' randy w
From the experienced old guy: I have had, in the past, issues with Girling seals turning into some form of soft flubber when "silly clone" is added. But not lately! The issue is the chemistry being non-compatible; make sure all the old stuff is gone, gone, flushed. My feeling is also that the newer seals are a bit harder compound and although they drag a bit in the control valve function, manage to swim well in the fake stuff. Still, after having done more than 300 of the little Girlings in 4 decades, it's a mystery when they work!! keepin' em' runnin' randy w