Burgie

Noted prior owner used Prestone Synthetic Super Dot 4 for Clutch fluid. GM sells a bottle of Super Dot 4 however it does not state if it is synthetic. Which is the preferred one to use. The GM one has it's label placed over a product that is made in Germany and sells it for 13 bucks a bottle.
What is the preferred type to use?

cclive

The Prestone DOT 4 Synthetic from Walmart is fine...and it's $4. I don't think that the word "synthetic" is descriptive in the case of brake fluid and is just added to the label because it is seen as a positive in motor oil. To me, it would be much more important to change the fluid using the Ranger method often enough to keep it the color of light honey.

John Harry

Yeah, my understanding is that all DOT 3 and 4 brake fluids are "synthetic".

cclive

Exactly...all brake fluid is "synthetic" by definition.

Dano523

Ditto, unless your fluid is pitch black, then it may be wise to do a power bleed through the slave cylinder to begin with, with the ranger method to keep the fluid clear after such

The fluid line from the master to the slave has 3 orifice restrictor's in line alone the path line, and although the ranger method will work for the most part after a few quarts of fluid changes (and a ton of pedal pumping), it can still leave debris (rubber and clutch pad dust) in the slave cylinder.

With powder breeding down from the reserve tank through/out the slave cylinder with a power bleeder, you get enough fluid cavitation in the slave cylinder to knock the debris into the fluid to suspend them and get such out of the system through the slave bleeder valve in about half the amount of fluid. The downfall, the bleed valve on the slave cylinder is not walk in the part to get to so you can power bleed the system.