Help me find highest boiling point dot 4 fluid

[EvanD]

My Car 01 camaro SS does not like being shifted at high RPM to quickly when it gets hot. The only fluid that I havent changed is the hydraulic clutch fluid. I suspect it's old by now.
What DOT 4 fluid has the highest boiling point??? I am fine with exotic fluids as long as it is a superior fluid.

castrol SRF is getting many good reviews. Very expensive stuff.
motul 600 is reviewed as absorbing water and need frequent changing.

 

[jaj]

High temp fluid that you change occasionally: Castrol SRF
High temp fluid that you change regularly but that doesn't cost a lot: Motorcraft DOT3

 

[expat]

Why do you think it's the clutch fluid?

Personally I would think it VERY unlikely that the fluid is overheating. But you may have air in the system.

What oils have you tired, or are using, in the transmission?

 

[cascivic]

I'm no expert but brake fluid used in a clutch master slave arrangement hasn't introduction to heat the way it does when used in brakes..it's purely there as hydraulic fluid and any full and properly bled fluid will net the same result.

If you switch fluid out and bleed and issue is still there could be clutch or throw out going south

 

[EvanD]

This is very common issue on these cars. Many people are drilling out the orifice in the clutch lines. It affects vettes and new camaros too.
Yes factory spec is dot 4

 

[dparm]

I believe Endless's fluid is the highest, followed by SRF and RBF600.

 

[tommygunn]

There is Prospeed RS683, but it's $80/L. As the name suggests, the dry BP is 683 and the wet BP is in the low 400's.

For something available in stores, go for Castrol Dot 4. Dry BP 509, wet BP 329

I also like Wagner SevereDuty DOT 5.1 (despite the name, it *is* compatible with DOT 3/4 and is NOT silicone). Dry BP 500, wet BP 356. Less than $20/qt on Amazon.

A lot of people also like ATE Type 200, which is Super Blue but without the blue dye that stains everything

 

[Ken2]

There are unofficial DOT4+ fluids with higher boiling points--the ATF fluids are one. And the DOT5.1 fluids which are very similar.

 

[expat]

What is the cause of the problem here?

Does the clutch MC come too close to the exhaust?

Whatever, It sounds like a design problem. Could shielding of some sort be a better solution?

 

[dailydriver]

I would go for something with the highest WET boiling point for a street driven, clutch fluid not changed very often, LSx f body.

The SRF (or whatever Castrol is calling it nowadays) was always the leader in this respect with an > 500*F WET boiling point, but as you've said, one does PAY for it!

There is also the U.S. made, Summit and Jegs available, AFCO HTX 600 with the same specs as the Motul RBF 600 (and a similar price point), which hopefully has a less hygroscopic rep than the French stuff.
And the NEO 610 fluid as well, with similar specs, and U.S. made.

Did you do the 'drill mod', and do you have a Tick, or other aftermarket master cylinder??
Which slave cylinder are you using?

Did you install a Tick (or whomever's) remote bleeder to the slave bleed port??? (One of the BEST mods I EVER did to my car- clutch bleeding/flushing is now a one person, < 10 minute job!!

)

 

[EvanD]

I have 28k miles so I want to do this job once and not again for a very long time. So a few extra bucks on fluid is ok with me.

Tick looks like the way to go. However, I am torn because the drill mod looks so cheap and easy. I am trying to decide. Aftermarket clutch must need more than the drill mod but on a stock clutch. I am unsure.

 

[expat]

OK, I found this explanation myself:

"The cause of the problem: the stock clutch master cylinder simply doesn't flow enough fluid to push the clutch slave cylinder far enough to fully disengage the clutch. This produces extreme heat inside the bellhousing, boiling the fluid inside the hydraulic system (thus introducing air) and causing a faded (or totally dead) clutch pedal. Other side effects include difficulty shifting at high RPMs, difficulty engaging 1st and Reverse while stopped, shortened clutch life and shortened transmission life. We've been seeing this exact issue for years in many applications.

Known Band-Aids for the problem: Notice we say band-aids, not fixes. These items may help your problem, although they won't solve it:

Tick Performance Stainless Braided Clutch Line (here)
Lingenfelter Clutch Pedal Return Kit (here)
Tick Performance Slave Cylinder Shim Kit (3 Pack) (here)
Keeping fluid fresh and free of clutch dust
Using exotic, expensive aftermarket hydraulic fluid
We've even seen some reservoir modifications, etc

Unfortunately, these items will only help ease the symptoms of the problem, best case scenario.

There is only one way to SOLVE the problem: by upgrading the master cylinder to move more fluid. Our Adjustable Master Cylinder kits that utilize a bigger bore cylinder have solved this problem in thousands of other GM applications (93-02 F-Body, 97-08 Corvette, 04-06 GTO, etc) but in 2009, GM changed the way the computer monitors the clutch master cylinder, making it impossible to use our kit as designed. This leaves 2009+ Corvette owners, 2009 G8 GXP owners and 2010+ V8 Camaro owners without a solution for the time being."

Looks like GM Goofed again!

 

[EvanD]

Well I placed my order. Before I break down and go for the tick master. I called Mcleod.

I placed my order.
Mcleod direct replacement line without restriction.
Motul RBF 660 only 17 for 500ml vs SRF 75 for a liter from Amazon.
Dei heat shield for the line.

I am hoping this will fix it back to normal. The bigger master has a lower engagement point and I am hoping to avoid this. I drive in city traffic with a size 15 foot. The last thing I want is a lower clutch pedal feeling.