Ivanrad

What type of brake fluid does the c320 2001 need ? How much ?

Glyn M Ruck

Any good DOT 4 fluid will do. You need a litre to do a flush.

SunnyRayToronto

Yes, as per manual, DOT4

But Mercedes-Benz Stealerships,.... are now recommending Dot 4+,... which is harder to find so you basically have to get it at the Mercedes-Benz Stealership,.... where they overcharge (about $25 in Canada),.... Dot 4+ MB part# A000 989 08 07 13

Dot 4 is good enough,.... Dot 4+ has slightly higher boiling point,.... so unless you're racing your car against F1 cars,.... you'll be fine with Dot 4

Hmmmm,... just like the Mobil 5W40 to Mobile 0W40,... now to Mobil 5W40 ESP,.... Why is it, every time we're looking for the right lubricant, Mercedes-Benz Stealerships expects us to bend over?

Glyn M Ruck

The downside to DOT4+ is that it is even more hygroscopic & thus absorbs more water. DOT4 is fine.

Moviela

I have noticed that there is only one approved brake fluid in my owners manual. The one Mercedes sells. I used the MSDS for that product and discovered it looks a lot like this one:

http://www.ate-na.com/generator/www/...d_SL6_US_E.pdf

Just using any Dot 4 or 4+ is not going to provide the performance necessary for specified operation of the ESP and ABS functions. These are emergency actions that should seldom be seen in daily driving, and they rely on high speed, high pressure operation of the brakes. The passages in the ABS unit are tiny and the viscosity of most DOT 4 products is too high at about 1400 mm2/s. The ATE SL.6 has a viscosity of 700 mm2/s.

http://www.ate-na.com/generator/www/...bf_sl6_us.html

I know that brake fluid likes to absorb water, but I don't see that as a major problem in modern systems. The vent to the atmosphere is a pinhole, and the surface on top of the fluid is quite small. I do see the boiling point of brake fluid in service dropping, but I don't think it is water causing it. I think evaporation of the 25% of the stuff is VOC's is the reason the boiling point goes down.

I also think the reason for changing the fluid every two years is not because of the water in the fluid. It is because of copper that is absorbed into the fluid. If allowed to remain it will cause corrosion.

I would be happy to hear Glyn's opinion on my thinking, assuming he can drag himself away from Pat Pong to do so.

Glyn M Ruck

Movie - Many of yours & Alfred Teves points are valid. Certainly viscosity can be an issue at minus 30 degrees. The fluid actually warms up pretty quickly due to the ABS pump.

The truth of the matter is that all major BF suppliers have dropped viscosity of even DOT 4 over the years - This is not new. These products could not be marketed without warnings displayed if they had a negative effect on ABS or ESP performance.

Loss of VOCs in the fluid, depending on composition could cause thickening & in some cases boiling point to rise.

Copper leaching & redeposition can certainly be a concern. It is more of an issue in refrigeration systems. Both refrigeration & braking component alloys etc used today are essentially copper free for this very reason & copper passivators form part of fluid formulation for a belt & bracers approach.

I still consider water, corrosion & their by-products to be the biggest killers of modern braking systems. Especially in ABS systems where the pump circulates the fluid. Benz ABS blocks do have small passages but nothing in the human hair range & most have accumulator/dampers in line

Ate makes fine products but so do many others. Viscosity, “dry boiling point” , “wet boiling point,” stratification & elastomer compatibility are still the major measures.

Most fluids exceed the minimum DOT requirements for a specific classification by a wide margin.

All should maintain their braking systems & observe Benz flush recommendations.

phister

I use ATE sl.6 or the super blue and haven't had issues. I've also tried Motul.

Ivanrad

well great.. i went to Napa Auto Parts and got Dot 4 Brake fluid Heavy duty . Says it meets FMVSS 116 and SAE J-1704
. Hope this will work. Planning on replacing the booster tomorrow, spoiler, and plasti dip grille. Hope i can finish all this tomorrow.

Carsy

Its good to buy a fluid with a different colour to the one in your system as you can see clearly when the fluid has been changed in each cylinder.

Ivanrad

Will this one work and not cause any longterm problems ?

Glyn M Ruck

It will be fine Ivan & says it's specifically for cars with ABS etc.

Ivanrad

Thank u glyn