• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Equivalent Brake Fluid

Got_All_4

Luke Skywalker
Country flag
Offline
I hate to bring up the brake fluid discussions again because I know what always happens but what prompted me to ask is I went into Team Triumph and purchased a rebuild kit today for my clutch master cylinder that went out on me last week. There was a new brake master cylinder on the counter from TRW and a big orange sticker that said if DOT 5 brake fluid was used it would void the warrantee. That started a discussion with the owner and me since I like to use DOT 5. I have it in my TR250's system. The clutch repair kit is also TRW made so I read the instructions in it and said to use what the manufacture recommenced. You can't find the Castrol Girling or GTX anymore and I know that's what I used in my TR3 when I rebuilt it back in the late 70's. However I don't know what I used a few years ago when I replaced the pistons in the front calipers.
 
Castrol GT/LMA seems to be routinely available at Pep Boys in the Albany, NY, area. If you have a Pep Boys, you might want to check them out. As for TRW not liking DOT 5? Well.... :devilgrin:

Unless the rubber seal formulation is vastly different under TRW than it was under Girling / Lucas, I can only note that hundreds of folks seem to have successfully used DOT 5 in their Triumphs with Girling / Lucas (/ TRW) systems. (Not me; I'm still a diehard GT/LMA fan m'self!)
 
:iagree:
with the caveat that a very few people have had trouble with freshly resleeved master cylinders not liking DOT 5. Apparently sometimes, when the clearances are a bit on the tight side, the piston can bind and not return properly.

ISTR someone reporting that just working the cylinder a dozen times or so by hand made the problem disappear.
 
The same warning came on my freshly rebuilt and SS sleeved master cylinder from Apple Hydraulics. Been working fine with DOT 5 for a couple of years now.
 
I've had success with Dot 5 with TRF rebuild kits, but not certain of their source.
 
Most likely because air bubbles are common with Silicone brake fluid and instead of getting the air out, the new master cylinder gets returned as "defective"
 
I just purchased 2 quarts of Castrol last week and the bottle looked different and said synthetic on the bottle, I ask the guy at the counter, which by the way was an import parts house and I asked was it still compatable with foreign cars like triumphs and he said yes

we will find out

Hondo
 
Doesn't Apple have a warning about Dot 5 because of that?
 
hondo402000 said:
I just purchased 2 quarts of Castrol last week and the bottle looked different and said synthetic on the bottle, I ask the guy at the counter, which by the way was an import parts house and I asked was it still compatable with foreign cars like triumphs and he said yes

we will find out

Hondo

That is because of the court case that Castrol won where they stated that anything made in a factory, processed, made by man etc... is Synthetic. The courts agreed so now Castrol puts Synthetic on just about everything. The Castrol GT-LMA with "synthetic" on the bottle is no different than the stuff without "synthetic" on the bottle. Synthetic does not = Silicone, especially after the aforementioned court case.
 
TR3driver said:
:iagree:
with the caveat that a very few people have had trouble with freshly resleeved master cylinders not liking DOT 5. Apparently sometimes, when the clearances are a bit on the tight side, the piston can bind and not return properly.

ISTR someone reporting that just working the cylinder a dozen times or so by hand made the problem disappear.

A tad off topic, but this is a known issue with MGA/Bugeye MC seals. After about 50+/- time being worked all will be well but it is a bit eye opening when you first experience it. As Randall said you just need to keep working the seals.
 
DOT5 has been in my TR8 for the past 10 years. I rebuilt the clutch system and the DOT5 went in. A few years later I did the brakes with new seals, SS lines, etc and that also got DOT5.

Knowing that bubbles can cause an issue, my bleeding process was a bit more aggressive.

I have never had a problem and have only had to rebuild the clutch master cylinder once since I switched....and I drive the car a lot.
 
swift6 said:
That is because of the court case that Castrol won where they stated that anything made in a factory, processed, made by man etc... is Synthetic. The courts agreed so now Castrol puts Synthetic on just about everything. The Castrol GT-LMA with "synthetic" on the bottle is no different than the stuff without "synthetic" on the bottle. Synthetic does not = Silicone, especially after the aforementioned court case.

I was searching on this the other week and there was a lot of great information in the Healey forum on this. I've gotten LMA at my local Pep Boys, too.

I "liked" Castrol on Facebook hoping to get updates like "Castrol LMA is still the same!," "Hypoy GL4-Now at Pep Boys!," and "We like old cars," but all I get is updates for John Force's drag racing team. :madder:
 
I have been running Silicone DOT5 in my Stag now for 8 years, supplied by Classic Tube. Flushed twice in 8 years with new fluid on brake service just to keep it looking fresh.

Zip - nada problems, no leaks.

The problems people have had were with DOT5 that was 100% silicone and no lubricants added. NAPA and the stuff sold by Classic Tube both have non ethylene glycol lubricants to keep the seals sliding properly.

Someone told me that some DOT 5 fluids do have Ethylene Glycol that attack natural rubber, so read the label first.
 
no fast driver would use that stuff as it gives a soft spongy pedal feel.
and it doesn't withstand heat too well in racing.

I use DOT4 or DOT 5.1 at my race car.

BTW...hydroscopic brake fluid is not a failure....they want the fluid like that to maintain a good brake when moisture entered the system. DOT 5 doesn't provide that.

Cheers
Chris
 
Back
Top