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Halon
03-29-2009, 08:33 PM
My car is a 1991. I have a very strong feeling that the brake fluid in this car is still the factory stuff. I also notice when pressing hard on the brakes, that the car pulls. Something I want to do is just completely flush out the brake system and get some new fluid in there.

I'm no brake fluid expert, so I'd like to hear what a good fluid to use would be. I've done some searching and it sounds like ATE makes some good fluid. But I'm not convinced it is for me.

This car is a summer toy, that I just toy around on the streets most of the time. See's very little track time. So, I'm not looking for the best Race Ready fluid on the planet. Whatever fluid I use, I would prefer to not have to replace it again at all soon, or in the next 5 years for that matter. I've heard that some of the better fluids may perform better, but don't last as long because of moisture. I'm trying to simply find a fluid that is a good compromise between performance, and longevity.

Open to any suggestions, but please keep my goal in mind. I don't AutoX the car or anything like that. Just some hard braking after a pull here and there, that's it. Would something like sythetic Valvoline stuff work?

MustGoFaster
03-29-2009, 09:02 PM
That synthetic valvoline stuff is what I run. Easy to find, and a good fluid to boot. Never had an issue with it, even at track days. But really, if your not going to put a ton of stress on the brake system, even the parts store generic stuff would work just fine.

As for the pulling, your going to want to check your brake pads, caliper slides, and pistons. If a slide or piston has stuck it will wear out the pads on one side, and then the braking forces are unbalanced so the car pulls. If the fluid has never been bled, it's going to be dark in color. New fluid is clear, with maybe a slight hint of yellow.

If the fluid has never been bled, if end up with water in it. It just absorbs it through the rubber and what not. And then it collects down in the caliper and rusts inside and makes the piston(s) stick.

Kracka
03-29-2009, 10:13 PM
Valvoline Synpower DOT4 is some of the best off-the-shelf fluid you can find at most stores and is more fluid than 99.9% of drivers will ever need. If you want to go a bit better b/c you plan on tracking the car there is ATE Super Blue (which is what I purchased), or even better yet, AMSOIL DOT4. MOTUL is also a popular choice, but it doesn't belong in street cars since its good for 6 months max. The better the brake fluid, the more expensive it is and the more frequently it needs bleeding/flushing. The Valvoline Syn is a good choice for you since its a high-performance fluid that will last for a few years w/o a problem.

sleepydsm
03-29-2009, 10:46 PM
Wouldn't just plain off the shelf DOT4 be good enough? Pulling to one side while braking, assuming your front end bushings are solid, would indicate a problem like a seized caliper slide or stuck pads.

deadeye
03-30-2009, 12:04 AM
As long as your running DOT4 your fine. It has to meet a minumum standard to get that rating so any fluid rated that way will work. The valvoline stuff has always been good and its pretty cheap so go for it.

MGF hit it right on with this one. As far as the pull goes, it may or may not have to do with the brake fluid. Given that you are thinking its stock stuff after 18 years it might a cause to a bigger problem. The fluid absorbs water causing the pistons/cylinders in the caliper to rust. This creates a slow/stuck piston which gives you less braking pressure on one side causing a pull. However you could have a stuck/sticky slide from lack of lube too. Tough to say without pulling it apart.

I would suck out the brake fluid in the M/C and replace it with clean stuff and then bleed the brakes until it flows clear. Start at the pass rear and work your way up. Then clean up the caliper slides and lube them up real nice and see what happens. If your lucky it will clear up the pull for less than 10 bucks. Otherwise a set of rebuilt calipers may be needed.

lucasoil4u
04-01-2009, 01:15 AM
i work at a parts store nd valovine dot4 is really good stuff that lasts a long time...i recomend it!

Speedfreak
04-01-2009, 01:32 AM
That synthetic valvoline stuff is what I run. Easy to find, and a good fluid to boot. Never had an issue with it, even at track days. But really, if your not going to put a ton of stress on the brake system, even the parts store generic stuff would work just fine.

As for the pulling, your going to want to check your brake pads, caliper slides, and pistons. If a slide or piston has stuck it will wear out the pads on one side, and then the braking forces are unbalanced so the car pulls. If the fluid has never been bled, it's going to be dark in color. New fluid is clear, with maybe a slight hint of yellow.

If the fluid has never been bled, if end up with water in it. It just absorbs it through the rubber and what not. And then it collects down in the caliper and rusts inside and makes the piston(s) stick.

Correct


Valvoline Synpower DOT4 is some of the best off-the-shelf fluid you can find at most stores and is more fluid than 99.9% of drivers will ever need. If you want to go a bit better b/c you plan on tracking the car there is ATE Super Blue (which is what I purchased), or even better yet, AMSOIL DOT4. MOTUL is also a popular choice, but it doesn't belong in street cars since its good for 6 months max. The better the brake fluid, the more expensive it is and the more frequently it needs bleeding/flushing. The Valvoline Syn is a good choice for you since its a high-performance fluid that will last for a few years w/o a problem.

Pretty much spot on.

niterydr
04-01-2009, 07:32 AM
Kracka, not to go off topic, but do you have a link for the Motul fluid expiring after 6 months? I never had a problem with it in my stealth and used it for a few years...
The valvoline dot 4 stuff is awesome for stuff you can get practically anywhere. That is what the Audi will get when a brake upgrade happens (2011, lol).

Kracka
04-01-2009, 08:02 AM
Swanny, it won't just "expire" after 6 months, but it absorbs so much water it drops the boiling point down below a safe level. Like any brake fluid (which generally lasts only 2-3 years at the most) you'll never notice when it goes bad on the street because the fact of the matter is most of us don't drive that hard on the streets and don't push the brakes that hard. But, if you needed to, with the old fluid, the brakes might not be there for you when you most need them. This is why most tracks (I'm not talking drag racing) require brake fluid to be fresh, and at the most, only 6 months old and not discolored at all to be considered safe.

Here is a quick link for you with some basic brake info. Its on EvoM, but it pretty much repeats all the same stuff discussed on auto-x, S2k, etc. forums:
http://forums.evolutionm.net/evo-tires-wheels-brakes-suspension-sponsored-tire-rack/390163-brake-rotor-pad-line-fluid-duct-thread.html

niterydr
04-01-2009, 12:13 PM
Swanny, it won't just "expire" after 6 months, but it absorbs so much water it drops the boiling point down below a safe level. Like any brake fluid (which generally lasts only 2-3 years at the most) you'll never notice when it goes bad on the street because the fact of the matter is most of us don't drive that hard on the streets and don't push the brakes that hard. But, if you needed to, with the old fluid, the brakes might not be there for you when you most need them. This is why most tracks (I'm not talking drag racing) require brake fluid to be fresh, and at the most, only 6 months old and not discolored at all to be considered safe.

Here is a quick link for you with some basic brake info. Its on EvoM, but it pretty much repeats all the same stuff discussed on auto-x, S2k, etc. forums:
http://forums.evolutionm.net/evo-tires-wheels-brakes-suspension-sponsored-tire-rack/390163-brake-rotor-pad-line-fluid-duct-thread.html

Sweet, well I will check this when I get home.