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Discussion Starter · #1 ·
As this car advised to fill with with Dot 3 only says on the reservoir-cap; however i heard that it can be mixed with dot 4 as long as it is mineral oil (not synthetic!!)

There is Dot 3 synthetic brake fluid so it seems. Can this be put in the Silver Shadow 1?

Does anyone know? :roll:





:idea:
 

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Absolutely not. I dont care what anyone says or advises but after 30 years with Rolls-Royce I have learnt you must use nothing else but Castrol 363. Other may "seem" to work but will cause problems "down the track". If you have already added "something else", I suggest you drain and re-fill with 363.

Rodd Sala - Park-Ward Motors

http://park-ward-motors.com/
 

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Hemmo,

If you want to stay with factory recommendations, and this is one case where I really think you should, use only RR363 brake fluid.

This is the only Crewe specified brake fluid for the SY series cars that predate the conversion to mineral oil systems. It is a DOT3 fluid that contains additional lubricating additives for the brake pumps, which were very prone to failure when Girling Green and Girling Amber DOT3 formulations were used. I believe yours is an early car, and the warning on the reservoir tanks was changed after the failures and reformulations of the fluid to arrive at RR363 were complete. This is all easily researched in the RROC-AustraliaTee-One Topics Archive and other RR/Bentley related sites on the internet.

Whatever you do, do not use straight DOT3 brake fluid for any extended period of time. I have used straight DOT3 when I am performing a hydraulic system flush/purge since it virtually all drains after that.

There are some who are using DOT3 or DOT4 fluid with castor oil added to it around 10% and I know of at least one person using straight DOT4, but in both cases the cars have not had sufficient time to determine whether brake pump failure will occur.

I would love to find a safe and functional equivalent to RR363, particularly one that is not hygroscopic like DOT3 fluids are and that does not require changing out the fluid every two years, religiously. RR363 is also ridiculously expensive as ours were the only cars to use it.

Were I really brave I'd consider experimenting with Texaco BioStar hydraulic fluid at the viscosity nearest to RR363. It's not hygroscopic, is derived from plant materials, and could work very well. Knowing what I know about the expense and difficulty of rebuilding the brake pumps, and the increasing difficulty of obtaining parts, I'm not really brave.
 

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Discussion Starter · #4 ·
Thanks, i see and i just "googled" about it.

Castrol RR363 has added castor-oil to lubricate the brake-pumps.

Haven't mixed it with anything yet.

I'll order it on EBAY.UK :idea:




:arrow:
 

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Discussion Starter · #5 ·
And thank you too Brian,

Castrol RR363 (1 liter) is for sale on EBAY.UK for 10,99 GBP, but postage is at least 6 GBP it seems. Anyway, i'll not be brave to try anything else.

My system only needs a little filling-up :)



BTW. My brake-cap says: Castrol girling green recommended





:arrow:
 

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brake fluid shadow 1

agree with what else has been said only use RR 363 on shadows . Dont forget the brakes system has approx 2500 psi in system when working so its not worth trying something,better to be safe. Castrol girling Green was what was originally used this was replaced by RR363 The system should have been flushed and replaced with RR363. This would have been done in early 70's
 

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Brake fluid for SS

I have had a Silver Wright II 1980 since 1983 and I have used DOT 4 all the time. Every 2-3 years the brake fluid have been changed.
I have never had any leaks or problems with the brakes during all this years.I have never heard what is supposed to happen when you do not use the RR363.Anyone knows?
 

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363 vs Dot4

That's very interesting information.

We have carried out various experiments and determined that DOT fluids can work the same as 363, however we remained concerned about the long term effects of NOT using 363. Chemical analyses carried out by us showed that the main difference is the 363 contains a lubricant additive so we felt that this was/is important for the long term wear and tear and correct operation of the system. Because no long term tests had been taken by us, we took the position of NOT substituting the fluid and have since always continued to use 363. Perhaps now, with your long term test, you bring new information to the table. Would you mind emailing me directly at [email protected]

Kind regards,

Rodd
 

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This is an "issue" that will never be definitively settled to the satisfaction of everyone.

There are several well known facts:

- RR363 is a DOT3/4 compliant fluid (I think it's now DOT 4, too)
- The only stated difference between RR363 and normal DOT3 fluid is the lubricating additive, widely acknowledged to be ethoxylated-propoxylated castor oil at percentages between about 8 and 10 or so (look up the MSDS)
- It is hygroscopic (like all DOT3 fluids) and really must be changed at a minimum of once every two years
- The company is never going to come up with an alternative nor endorse one. These cars have been out of production since 1980 and there is no reason on earth for them to do any R&D related to a brake/hydraulic system they haven't produced for just short of 35 years.
- Citroen owners have been experimenting with concoctions for a while now, and our systems are really not all that different from theirs

I personally know of:
- One person who's been using Prestone Synthetic DOT3 fluid exclusively for 8 years without any issues
- Three people who've been using a 90/10 DOT3 (or, in one case DOT4 Castrol GT LMA) brake fluid to pharmaceutical grade castor oil mix for 6, 5, and an unknown period of years without issue

I have conducted my own "on the shelf" experiment with a 90-10 DOT3-pharmaceutical castor oil mix for about 5 years to see if it would separate or coagulate under any conditions we normally see where I live (and, barring a polar vortex, we seldom reach even single digits F here). The stuff has remained entirely stable for that entire time in a bottle that allows me a clear view of what's happening.

This past spring when I did a rebuild of the accumulators on my Shadow II I decided that I had enough data to feel comfortable using the 90/10 mix discussed above.

The purists will insist that RR363 is the only factory recommended fluid, and they are right. There have been problems with supply of RR363 in the recent past and a "bad batch" that came out in the mid-2000s. In my mind, the writing is on the wall that RR363 is not going to be in perpetual production.

As is so common with any collector car past "a certain age" it becomes the task of the community of collectors to figure out "what works now" when so many fluids, lubricants, etc., that were recommended at the time of manufacture no longer exist.

You have to do your own homework, read quite a bit, and come to a decision you're comfortable with.

Brian, who also uses 2-EHA-free long life coolant in both my SY cars without issue (contrary to the roars of those who insist that only the old-type IAT "green stuff" is the only safe coolant to use) and the latest SN service rating motor oil, too (read the SAE and ILSAC specs and you know that this oil is perfectly fine for our cars)
 

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I just bought a 1977 silver shadow and the 2 brake pressure light came on. Does this mean I need to have the rear brakes redone and flush the fluid out to make sure the correct rr363 has been used?
 

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As this car advised to fill with with Dot 3 only says on the reservoir-cap; however i heard that it can be mixed with dot 4 as long as it is mineral oil (not synthetic!!)

There is Dot 3 synthetic brake fluid so it seems. Can this be put in the Silver Shadow 1?

Does anyone know? :roll:





:idea:
I HAVE AN INTERESTING STORY TO TELL. I HAVE RESTORED ROLLS ROYCE TOYS FOR 35 YEARS AS A HOBBY! NO, I DO NOT ADVRTIZE and not the how much cash do you have crowd) ( cause I am going to soak you, you own a rolls). in Germany a client purchased a shadow series 1969. first thing he notice the metal emblem attached to the top of the brake fluid tank. ( use dot 3 yellow ). In my rowing travels I made it a point to discover other shadows which had the same emblem in Germany. These vehicles obviously sold new by a German Rolls Royce dealer. . I LOVE THE SHADOWS ESPECIALLY THE II SERIES. I have to say everyone i have serviced never had the brake fluid changed in many years.. and in that line of thinking and the goop build up. i have intelligent clients that use dot 4. they drain the system at intervals and their systems are clean!. as far as the lubrication aspect of 363/ what good is it in dirty fluid over 10-20 years? the old school owners when the club was grand to belong too, they had some moxie! they just added dot 3. as far as i know still do and doing fine.
 

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The lubrication component is really to satisfy the 2 brake pumps which are constantly moving and face heat from the motor.
 

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I know a member on the Australian RR Forum who flushed and vacuumed the hydraulic system in his Bentley T and has been using DOT 5 for many years. Every couple of years he drains, filters and reuses the same DOT 5. He's experienced no problems and believes that DOT 5 - being fully synthetic and non-hydroscopic - is better than RR363. However, since DOT 5 does not blend with DOT 3 or DOT 4, old fluid is vacuumed from the system before DOT 5 is added. He assembled his own vacuum extractor using a demijon glass jar but I'm not sure exactly how the vacuum is created. The usual caveat "do this at your own risk" obviously applies, I haven't tried this method myself but it's something that I might consider doing in the future. If I decide to go that route I think I would bleed off some of the DOT 5 at the extremities of the system occasionally (at the callipers, height control bleed screws and pressure switches) to expel any possible water collection at these end of line points.
 

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Even though I don't own a Shadow, I use DOT 5 in my Mark VI and Jaguar, now even though my cars are no where near as complex as a Shadow, it makes perfect sense to use a non-hygroscopic fluid.
Every time one opens up the very large lid of the reservoir in a Shadow, it exposes all that surface area to the moisture in the air.
It just seems like the whole thing wasn't very well thought out, demanding perpetual maintenance.

The whole system is no different then any hydraulic system that may be in a heavy machinery or a hydraulic press where oil is used, and yet the car uses brake fluid.
Rolls Royce should have at least come up with something that doesn't attract water.
 

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It's not just opening the lid of a Shadow brake fluid reservoir, it's the constantly changing barometric pressure that forces moist air in and out of the reservoir filler cap vent holes. If RR had made a convoluted rubber bladder that covers the surface of the fluid in the reservoir that would have greatly lessened the amount of moisture absorbed by the brake fluid. Chrysler for one figured that out in the 70's.
They did eventually change to mineral oil for a brake fluid in 1980, but I still find water contamination causing corrosion of the caliper pistons in those systems when they are neglected.
 

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DOT 5 is worse since it doesn't absorb water as easily but allows it to collect in nooks and crannies and worse to remove. I would rather stick to DOT4 with PharmaCaster mix.
 

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I agree that DOT 5 doesn't absorb water like DOT3 or 4 and that it allows the water to stay separate and collect in nooks & crannies but those nooks & crannies are normally at the ends of the brake lines & suspension lines where the bleed screws are located so bleeding off a small amount at more regular intervals should expel any water that has collected whereas with DOT 3 or 4 the water permeates the whole system necessitating regular flushing and bleeding of the complete system rather than simply bleeding off a small amount. There's also a cost saving benefit with DOT 5 insofar as when flushed it can be filtered and reused. I wonder if a disposable or cleanable water separation filter (something like what's used on diesel fuel systems) would help solve the problem?
 
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