Question on brake fluid castrol vs. valvoline

[glbft1]

Hello all,

Well blew my slave cylinder am going to install a new one tomorrow, searched high and low for castrol lma none to be had so grabbed full synthetic valvoline excceds dot 3-4 and full syn will this work going to mix with the castrol??



Thanks
Greg

[albersj51]

Someone with far more knowledge than I will chime in soon, but I would stick with LMA (what you have may be LMA), I just feel more comfortable when the bottle says it. on mine the shop I got it from redid the brakes because the PO mixed DOT something with LMA and ruined the system. I know pepboys here in sc carries castrol LMA for about $9. Best of luck!

[TedW]

Hello all,

Well blew my slave cylinder am going to install a new one tomorrow, searched high and low for castrol lma none to be had so grabbed full synthetic valvoline excceds dot 3-4 and full syn will this work going to mix with the castrol??



Thanks
Greg

Greg:

IIRC you can get Castrol GTLMA at VIP Discount Auto. I see it around all the time.

[disco2hse]

Flush the whole braking system. It doesn't matter then what you use.

Put it another way. You need to flush out all the old fluid and replace with new. That is more important.

[TeriAnn]

Someone with far more knowledge than I will chime in soon, but I would stick with LMA (what you have may be LMA), I just feel more comfortable when the bottle says it.

If it helps, LMA stands for low moisture absorption. The LMA fluid is designed to be less hygroscopic that other fluids which means your system lasts longer in moist environments without corrosion. Rover specifies DOT4 LMA for their Series brake systems.

Of course what you use is up to you.

[I Leak Oil]

Last I knew LMA was also recommended to avoid damaging (disolving) the seals in the system. Is this no longer the case? Am I antiquated at the age of 39 1/2 already?!

[bpj911]

fluid

I never could find any of that. I just used regular brake fluid and don't notice anything. Just started my second year of series ownership so it's not exactly long term testing. I am certainly not going to worry about it though as the wheel cylinders I have looked at have the same cups you can buy at Napa for pennies.

[SafeAirOne]

Castrol LMA is carried by PepBoys.

Last I knew LMA was also recommended to avoid damaging (disolving) the seals in the system. Is this no longer the case?

Uh Oh...I feel a lenghty debate coming...

Am I antiquated at the age of 39 1/2 already?

Maybe. Is your seal leaking?

[I Leak Oil]

That's kind of a personal question now isn't it? Oh your probably talking my brake system. I've used Castrol LMA since i've owned it and no leaks, no bad seals, no black chunky fluid....unlike when I bought it.

[rejeep]

when i replace fluid I always used dot 5...
its LMA, synthetic, and lasts a long time while being nice to seals...

I do believe the key is to make sure you purge your system from whatever was in there last..
if your using all new parts then its not such a big issue.

[Andrew IIA]

<snip> Rover specifies DOT4 LMA for their Series brake systems<snip>

I confess little knowledge of brake fluid specs, but my SIII manual specs DOT 3 as the proper stuff, so that's what I've been using (my SIIA has an SIII brake system).

Scan of SIII shop manual brake fluid spec:

[disco2hse]

I do believe the key is to make sure you purge your system from whatever was in there last..
if your using all new parts then its not such a big issue.

Yes. That is correct.

I confess little knowledge of brake fluid specs, but my SIII manual specs DOT 3 as the proper stuff, so that's what I've been using (my SIIA has an SIII brake system).

Scan of SIII shop manual brake fluid spec:

And since DOT 3 was released there is now also DOT 4 and Dot 5, which are improvements that take into account issues such as overheating braking systems. Over heating (and consequential brake failures) is more important than how much water might build up in the brake lines, unless of course you are in Seattle.

[bpj911]

DOT

DOT 3 and 4 are compatible with each other. dot 5 is silicone based. not compatible with anything. Dot 5 seems to work well long term if you always carry your own and flush it a little every once in a while. It's not hygroscopic so water will accumulate at the low points rather than mix in with the fluid throughout.

[Alaskan Rover]

NOTICE:
Don't use Castrol GT LMA Brake fluid! I repeat: Don't use Castrol GT LMA4.

They've changed their formula, as I've found out the HARD way. The new formula DOES deteriorate the natural rubber seals in Rover brake systems.

Rovers North now has started selling Genuine Land Rover brake fluid that does not eat up seals.

I used to use castrol GT LMA fluid ALL the time on my series IIA without problems, but as soon as I started using their "New and Improved" formula, I've had MANY problems with deteriorating seals and wheel cylinder cups and will now have to do much replacing!! I'll purge out ALL of that Castrol after that expensive mistake.

EDIT: Within 2 weeks after putting in the NEW Castrol GT LMA brake fluid, all my fluid turned black...a sure sign that your seals are being eaten away. luckily I didn't add any to my clutch master cylinder! Castrol basically turned their backs on all older English vehicles still using natural rubber seals when they went with their new synthetic formula...they went where the money is: Audi A8s and such.

[TedW]

Within 2 weeks after putting in the NEW Castrol GT LMA brake fluid, all my fluid turned black...a sure sign that your seals are being eaten away.

Anyone else experience this?

Oh, and thanks Alaskan Rover for bringing this up. As if we didn't have enough to worry about. First Egypt explodes, and now THIS!