DOT 3 Brake Fluid

[MrBoroHachi]

I believe all dot 3/4 fluid is synthetic now. My friends Yaris was 3-4 years old when I brought up the fact that he had the car for a little bit and had not flushed his brake fluid yet.

The fluid was just slightly more golden than the new fluid.

He just about crapped his panties at how more responsive the brakes were when I was done

 

[goatfarmer]

I believe all dot 3/4 fluid is synthetic now. My friends Yaris was 3-4 years old when I brought up the fact that he had the car for a little bit and had not flushed his brake fluid yet.

The fluid was just slightly more golden than the new fluid.

He just about crapped his panties at how more responsive the brakes were when I was done

I believe this may be the 1st time, since I drove the T4r of the show room floor, that I have actually purged the system, how embarrassing is that?

Had the option of purchasing the Dot 4 in either non, or synthetic, same brand? Decided on the non, to the best of my recollection, it's the type used in my T4r at the time?

 

[Immrtl86]

Cap recommends DOT 3. Replaced the rear brake cylinders, the fronts not. Intend flushing as much of the old fluid as possible; since I do not know whether synthetic fluid was used in the past whether switching to synthetic from NON synthetic fluid would be an issue??

I am under the impression that brake fluid, unlike motor oil, has always been a synthetic, rather than petroleum based formulation, i.e. polyglycol. The only exception to this is DOT 5 brake fluid which is silicone based.

Some brands now have marketing ploys that label brake fluid as "synthetic", but brake fluid has always been synthetic. DOT4 exceeds DOT3 requirements and can be used instead of DOT3. DOT5 fluid (silicone based) cannot be mixed with polyglycol based products.

 

[goatfarmer]

I am under the impression that brake fluid, unlike motor oil, has always been a synthetic, rather than petroleum based formulation, i.e. polyglycol. The only exception to this is DOT 5 brake fluid which is silicone based.

Some brands now have marketing ploys that label brake fluid as "synthetic", but brake fluid has always been synthetic. DOT4 exceeds DOT3 requirements and can be used instead of DOT3. DOT5 fluid (silicone based) cannot be mixed with polyglycol based products.

I am the personification of 'ole school' technology so in posting the question; non synthetic vs synthetic, my mind set was in reference to petroleum products on early model vehicles? Recharging the T4r brake system, assumed I should stay with the same flavor fluid currently in the system and not risk damaging brake rubber components; now know better, except perhaps with Dot 5?

Greatly appreciate the info!!