Brake Fluid Question DOT 4+ ML320
 

So I figured it is time to replace all my brake fluid in my fleet.
The Cap on the Master Cyl on my 1999 ML320 reads Dot 4+

At Auto Zone the counter guy said Dot 4+ means DOT 4 synthetic.
He sold me Valvoline Synpower DOT 3-4.

I guess Valvoline has a formula that can be mixed with 3 or 4 .

Anyone use this with success ?

I think you would be ill advised to put any synthetic or part synthetic brake fluid in any or your Mercedes Benz vehicles.

Brake fluid
 

Why do you say that Ron ?

what does DOT 4+ mean if that is not synthetic ?

Steve,

Read the posts in this link.

http://www.peachparts.com/shopforum/showthread.php?t=118115

The stuff I use has a boiling point of 536 degrees and wet boiling point of 392 degrees which is very good. Lots of people use this fluid in their Porsches both on the track and on the street.

Dot 4+ fluid
 

I flushed my brake fluid last month and the parts place (PepBoys) had the DOT 3/4+ fluid. I think it was Prestone.

Anyway, I'm about to flush the fluid in the volvo but purchased the fluid at Kragen. The Valvoline "synthetic formula" says it exceeds DOT 3 and 4 standards, and is "Compatible with conventional brake fluids". So now I'm really confused. :confused: Since it doesn't say 4+ I think I'm going to return it.

My bikes use DOT 5 and I know you don't mix it with other fluids.

brake fluid 4+
 

I used the Valvoline DOT 3-4 synthetic. No ill effects. (1999 ML320)

Ditto. Look for a DOT4 fluid with the highest wet boiling point, which is Valvoline where I shop. Brake fluid will absorb moisture in a street driven car, because you're going to leave it in for two years. On the track, look for the highest dry boiling point, since you're going to change it between each event.

Valvoline's "synthetic" name is pure marketing.

I believe DOT5 is silicone brake fluid, not mineral oil. I don't think you can consider it "synthetic", and it's not compatable with mineral oil.
I'd go with the MB brake fluid.

Gilly

MB Brake fluid
 

ALL,

This is not the place to squeeze the nickle, so to speak. Your life, and the life of your family depend on full braking function!

Your local MB Steelership will sell you the recommended fluid for just about 10 bucks a litre. That' enough to seriously flush one ABS system and maybe two, if you have a pressure bleeder.

Regards,

Jim in Phoenix

dot 4+
 

Dot 4+ or Super Dot 4 is lower viscosity than Dot 4. Dot 3 has a lower boiling point than Dot 4. I would use the Mercedes fluid or Pentosin Super Dot 4. I wouldn't use anything else.