| 294 Which brake fluid?
 Bob 
Owen has produced an excellent article which sets out the facts with a dispassionate 
assessment of the issues so fellow members can understand the DOT categories, 
the DOT fluid performance tests and the benefits and disadvantages of each fluid. 
He has also highlighted some concerns - key variables where there is uncertainty. 
In essence they are the lack of information on the composition of the replacement 
rubber seals and the effect of various formulations of glycol fluid available 
in the market on those different types of rubber seal - and the effect of silicone 
fluid on them too. They are being examined and a further report will follow. (Jan 
09)
 
 Whenever 
the topic of silicone brake fluid as a replacement for glycol is raised amongst 
classic car enthusiasts you soon see that some of the key issues and even some 
of the facts needed to make a balanced assessment are either not available or 
not sufficiently clear. So in the end each classic car owner has to make their 
own decision whether to change to silicone or stay with the original fluid, glycol. 
That decision is based on either their own view or, where they do not feel qualified 
or able to form a view, they will usually rely on the recommendation of the specialist 
who services their car.
 
 The 
choice of fluid is a topic that does attract firm views from some quarters and 
in a few cases the assertions of the merits of silicone as a replacement brake 
fluid are made with a zeal that worries those who would prefer to see the issues 
more calmly presented and assessed. Well, when the topic reached this stage in 
a bulletin board thread on the V8 Register's website last November, it was felt 
an impartial article setting out information derived from original sources rather 
than hearsay would provide fellow members with the facts and other information 
as a basis upon which to make their own decision on "which brake fluid to 
use?" Bob Owen was approached by the chairman of the V8 Register to do the 
research and prepare the article as he had
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 previously 
contributed a number of useful workshop notes and, whilst not a brake expert, 
he has a good understanding of physics from his electrical engineering training 
and has had a love of all things mechanical since he was a boy with a father who 
ran an agricultural engineering business. Equally Bob can claim to be impartial 
as he has some personal experience of both types of fluid having a 1974 MGBGTV8 
using standard DOT4 glycol and a 1949 MG TC converted to DOT5 silicone fluid some 
five years ago.
 Bob says "this article is an attempt to provide 
all the information you need to enable you to make your own choice of fluid". 
As the article is lengthy, some six pages, it has been published on the V8 website 
and available as a download at:
 www.v8register.net/subpages/brakefluidarticle1.htm
 
 Please note the content of this article is subject to the important 
caution and caveats set out at the end of the six page article
 Download 
a copy of the brake fluids paper. More
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