Dot 3/Dot 4 Brake fluid - United Bimmer Community

**jms** · 12-23-2005, 10:53 AM

I went to the local auto parts store to buy brake fluid for an upcoming flush (in about an hour) I asked the clerk if there were any other dot 4 fluids available, they only had 1 marked as dot 4. He told me that there is no difference between dot 3 and dot 4. And recommended the dot 3 prestone.

I bought the bought the dot 4 marked bottle it was about twice the cost, but I didn't want to take chances with having brake fluid issues. I mean they put the dot 4 on the label for a reason didn't they? I'm hoping it wasn't to just get me to spend twice as much. And if that was the case why didn't everybody have dot 4 on thier label?

The big question is, was the clerk right? Is there really no difference between the two fluids?

( I didn't order the superblue because I have to get this done before I leave on vacation - whole seperate issue)

**Rooz** · 12-23-2005, 11:03 AM

get somew RBF 600 fully synthetic brake fluid

**c1apton** · 12-23-2005, 11:23 AM

The clerk is a clown. The difference between them is DOT 4 is hi temp, hi pressure and has additives to resist moisture.
Also: AVOID synthetic's if you plan on ANY driving through high altitudes. Synthetics have similar properties as DOT 4 plus the benefit if spilled, it won't remove or damage your paint. Street rods & motorheads use it when they have painted & pinstriped frames. The Military did tests on syns and found in altitudes of 6k ft and above, it will compress up to half of it's volume size.

**xsperf** · 12-23-2005, 01:52 PM

haha, compress to half its size... lol and brake fluid too, real genious

.. but then again 6K ft is pretty high

if the label on your CAR says dot 3, use dot 3, or if it says dot 4, use dot 4, i remember one of my bros audis, one time he was in need of brake fluid and he can only add the audi brake fluid(the 25 dollars a bottle from the dealer) because when he tried adding the other stuff it started actin funny and was leaking.. very interesting

Storamin · 12-23-2005, 03:45 PM

Don't use synthethic... don't use dot 3...

Use ATE Super Blue or ATE Gold. (They're the same thing but different colors.)
Apexperformance.net is located in western PA and is at BeaveRun motorsports... it's where I buy mine at.

I've done brake fluid changes before and have a nice Motive power bleeder. If you need any help I'm up for it.

Edit: I wouldn't bother doing it before you leave if you can't use the right fluid. Do it afterwards with the new fluid.

**Hoppy** · 12-23-2005, 10:11 PM

and if it says use girling, laugh your ass off. and go buy some vegetable oil

sorry, a Triumph flash back

**Dudesky** · 12-29-2005, 05:34 AM

To add to this, I read that DOT 4 is standard for Bimmers which have anti-lock brakes.

**RealBmw 02** · 12-29-2005, 01:20 PM

To add to everyones great comments, never user DOT 5 on a car that wasn't factory shipped with it. DOT 5 is silicone based and will leak in every system that was not puposely designed and built for it. DOT 4 is all you will ever need for the street and even some track driving.

**jms** · 12-31-2005, 11:11 PM

I figured, I am using dot4 and it works, I had her in the shop for something else so I had him do the flush with dot4.