99Hawk#196

I am going to have the fluid changed in my clutch hydraulics and bought 2 qts. of Valvoline synthetic brake fluid(it states that it surpases DOT 3 & 4 requirements).

My 2 questions are:

1) someone pointed out to me that your not supposed to use "synthetics"...is this true??

2) how much fluid will I need to flush/bleed the system?

TIA

Tom <img border="0" alt="[Firebird]" title="" src="graemlins/formula.gif" />

Silver Slayer

iTrader: (13)

DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!

I cannot stress enough, do not use Valvoline synthetic!!! I used that fluid and have had nothing but problems since. I do not know about any other synthetics, but my hydraulics have not been the same since I filled my system with Valvoline synthetic. I swapped back to non-synthetic.

I would suggest going with a non-synthetic fluid, just to be on the safe side. I can't tell you exactly how much fluid you will need, because it varies with how much bleeding you have to do to get all the air out.

Again, do not use that fluid,
I hope its not too late.

Kevin

DERTY

DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!
DO NOT USE THAT FLUID!!!!! TAKE IT BACK!!!

That's damn right, that **** has ate my master cylinder up. In talking with the tech line at McLeod, just use the standard GM mineral based DOT 3 only. The cups on the piston in the master will break down when certain fluids contain some nice chemicals. While we aren't sure entirely, the Valvoline Synthetic is showing symptoms that he's heard about from other fluids. In this case the synthetic is not worth 5 extra HP, so go with the normal stuff!

99Hawk#196

Thanks guys!

I have a possible problem with vapor lock(the synth. stuff says it deals w/ that)in the clutch hydaulics.

Due to your response I will take it back or can I use it in my '97 Tahoe w/ $65K miles to flush the BRAKE lines(it said it 'enhances'ABS sys.)

Back to the vapor lock thing. Should I just get 'Heavy-duty' DOT 4 brake fluid?

Thanks again!

Tom <img border="0" alt="[Firebird]" title="" src="graemlins/formula.gif" />

DERTY

Just use a GM Dot 3 Mineral Based clutch fluid. You could also try to find some ATE Super Blue brake fluid. It's mineral based as well. That's all you need, nothing extravagent.

The Valvoline fluid may work fine with your brakes, but again I would double check to make sure that this crap won't eat your seals. From what I can tell this stuff loves to eat some of the seals up. Not saying that effects all seals, but you'll certainly feel it in the clutch pedal.

DERTY

I actually ordered a master cylinder rebuild kit from McLeod. It was $30 bucks plus shipping. Includes everything I need to rebuild the guts of the cylinder (plungers, etc.). I'm expecting that this week and I'm going to rebuild it. I bet you wish you knew about that before you went through three of them!!

But, you'll never guess what happened yesterday, the clutch return spring actually broke on my pedal. I now have half the spring in my cup holder and the other half is still on the clutch. Sounded cool when it broke. The spring bounced off all the metal under the dash making some cool noises. I'm going to get that fixed tomorrow morning. I'm not sure if that spring failing causes any issues at all as far as firmness and feel go. I'm not sure until I get the new one in.

The last thing I'm going to do is replace the pyroil fluid I just put in with some ATE Super Blue brake fluid. It's worth a try. Since the Pyroil is not mineral based I want to get rid of that crap too.

99Hawk#196

[QUOTE]Originally posted by derty:
[QB]Just use a GM Dot 3 Mineral Based clutch fluid. You could also try to find some ATE Super Blue brake fluid. It's mineral based as well. That's all you need, nothing extravagent.

Not to beat a dead horse(I really appreciate the responses). The key word is "mineral-based". Would DOT 4 be considered extravagent?

Anybody know where to get ATE Super brake fluid?

Tom <img border="0" alt="[Firebird]" title="" src="graemlins/formula.gif" />

DERTY

You really have to read the bottle for that particular oil. The ATE fluid says mineral based right on the can. Valvoline is Dot 3 / Dot 4, but it's not mineral based. The Dot 4 Pyroil I bought is not synthetic, but it's also not mineral based (at least it doesn't indicate that on the bottle). I really can't say that a Dot 4 is going to be mineral based. The GM Dot 3 brake fluid does come mineral based. I'm not sure if it comes in any other flavor though. I'm looking for a place to buy ATE online. But a performance parts store may have it as well.

Ben99Z28

I have been using the ATE Superblue fluid on both my brake and clutch for about 2 years, excellent dry and wet boiling point, they can last up to 3 years before you need to flush it again, it doesn't absorb water/vapor as easily as most fluid out there, good stuff!!!! <img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" /> bought it from local performance shop like $8/qt.

DERTY

You can buy the stuff online at http://www.autotechnic.net/store/asp...sp?product=125

I just ordered some. It's 8.95 plus shipping. Shipping is a bit steep like usual, but I don't want to waste my time looking around for the stuff here.

99Hawk#196

I got to find a performance shop <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> . The ATE stuff is $8.95 a liter, but the shipping was $8.88 <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

Tom <img border="0" alt="[Firebird]" title="" src="graemlins/formula.gif" />

Silver Slayer

iTrader: (13)

Derty,

Did you ever get your problems straightened out?

Kevin

Silver Slayer

iTrader: (13)

Derty,

No I did not know you could order a rebuild kit for the master cylinder. I will keep that in mind in case a new pressure plate does not totally solve my problem.

Thanks,
Kevin

MelloYellow

I've had no problems running the Valvoline Synthetic in my clutch hydraulics over the past year. It held up much better than the stock fluid. I'm switching to Motul 600 Dot 4 in the next week or two.

I'm also going to wrap the master/slave clutch line with Earl's Flameguard. My long tubes are cooking the fluid. Much heat hits that line.

99Hawk#196

"I'm switching to Motul 600 Dot 4 in the next week or two."

"I'm also going to wrap the master/slave clutch line with Earl's Flameguard. My long tubes are cooking the fluid. Much heat hits that line."[/QB][/QUOTE]

I think I'm just going to get 'Prestone DOT 4' brake fluid, but the wrapping of the lines sounds like a good idea. I don't have long-tubes, do you think it might be over-kill for me?

Tom <img border="0" alt="[Firebird]" title="" src="graemlins/formula.gif" />

<small>[ August 23, 2002, 10:25 AM: Message edited by: 99Hawk#196 ]</small>

99Hawk#196

ttt

MelloYellow

I think it's a good idea. My chevy mech has seen good results trying it on other cars. Check out this link for different line wrap ideas. Earl's Flameguard is great, but expensive and hard to find.

http://forums.corvetteforum.com/zerothread?id=368567