Sgtblue

iTrader: (16)

Did a search and found a comment from a member suspecting a recent change to synthetic brake fluid contributed/caused an ABS pump leak. Now the comment was a couple of years old and I didn't find where anyone else had a similar experience but again, the thread was (I think) from 2001.
Here's my particular situation:
I bought my FD a little over a year ago and while the brake fluid "looks" OK, I'm getting a set of speedbleeders want to do a complete flush, including the clutch slave and adding stainless lines. I've seen the names Motul etc. in my search but can't find it over the counter where I live. My car is limited to street use and I'm considering what appears to be a quality shelf synthetic like Valvoline. I'd appreciate any comments/experience of the possible detrimental effects of switching to synthetic brake fluid.
Apologies in advance if my search was wrong and this was another one of those beat-to-death topics.
Thanks, Jim

Mahjik

iTrader: (1)

Here's a brake fluid comparison:

http://www.swedishbricks.net/700900F...Comparison.htm

I would recommend Super Blue. Fluids like Motul are great for the track, but require more maintenance than the others for normal street driving.

Sgtblue

iTrader: (16)

Thanks Mahjik. Have you ever heard of problems with leaking pumps etc. after switching to a synthetic? I heard of snthetic oil maybe contributing to leaking turbos, but anything similar with brake fluid?

Mahjik

iTrader: (1)

Generally, synthetic oils are a little finer than dino oils; so if there are any tiny leaks in your oil system, synthetic oils will find them where as dino oil may just clog them up and not leak. Technically, it doesn't cause the leak, it just exposes it.

I've never heard of this happening with brake fluid.

maxcooper

The issue with brake fluids, as I understand it, is mainly between silicone and glycol based fluids. Silicone (a.k.a. DOT5) is not compatible with glycol fluids and may be more (or less) likely to cause problems with other parts of the system (seals, corrosion of metal parts, etc.). Most fluids (DOT3, DOT4) are glycol based and are just fine for most applications (including the FD).

There are DOT5.1 fluids that are just fine in the same way that the DOT3 and DOT4 fluids are, IIRC. The only fluid I know that is incompatible with more pedestrian fluids and other race fluids is the AP600 fluid, but I don't know the details of the incompatibility.

I'm not really sure in what way the term "synthetic" applies to brake fluids. I don't even know which fluids would be considered synthetic (including the Valvoline SynPower brand of fluid; synthetic? I don't know -- it might just be a branding thing). SynPower is cheap and available and I think it is a great solution for cars that don't need really extreme fluids. I have used it in my car and never had any trouble with it. Castrol LMA and some kind of Ford Hi Performance fluid are also reported to be good choices that you can get locally without braking the bank.

I currently use ATE Super Blue and I've got some ATE Typ 200 (amber version of Super Blue) for my next flush. It has a higher boiling point than the locally available stuff, doesn't cost too much, comes in two colors which is nice for flushing, and is supposed to last a while before it soaks up too much water (which seems to be the downside with running race fluids on the street).

-Max

Sgtblue

iTrader: (16)

I've read the comparison thread provided by Mahjik and it appears that Valvoline has decent performance for a shelf fluid. I haven't seen the ATE around here so I probably go with Valvoline this time around, just for the convenience. In another year or so, with the speedbleeders in place, I may switch to ATE.
Max...Re-checking the Valvoline label they specifically advertise that it's a "synthetic formula". Also from the label: "Contains: Brake Fluid (a complex mixture of glycol ethers, polyglycols and inhibitors". I'm not a chemist or engineer, so your guess is certainly better than mine on what that means. LOL, maybe the synthetic is all in the "complex mixing" part.
I did notice that they advertise slightly different numbers than in the comparison: 502 Dry and 343 wet.
Thanks again to both of you for the response.
Jim