jcynyc

Hi,

I have a 2001 A6 4.2L, and it looks like I'm going to need to buy some brake fluid. What's the best one to buy for my model?

Thanks.

jcy

2.7Lturbo

DOT 5....

4Driver4

Not DOT 5. DOT 4 is the best bet.

2.7Lturbo

lol yeah NOT DOT 5, thats silicone.... 5.1 however

jcynyc

Does it not matter which brand I get? Valvoline, prestone, etc?

2.7Lturbo

in the grand scheme of things? no....

Just Me

For day-2-day driving, it really does not matter much. All DOT 3,4,and 5.1 fluids are compatible. DOT 5 (not 5.1) is silicone based and cannot be used ever.

You should compltely flush your brake fluid every ~ 2 years.

Here's something that is rarely discussed. The higher the temperature of the fludi, all things equal, the faster it absorbs water. Water is the enemy of boiling point and causes corrosion. So buying super duper race fluid for the street is counter-productive.

For 99% of applications i suggest Castrol GT-LMA which has a good wet and dry boiling point, sufficient for all but hard track use, and is designed to absorb water more slowly. LMA = low moisture activity.

Regrettably my track habit means i cannot use it any longer.

Grant

Airbag

i use ate superblue in my audi and porsche. no complaints whatsoever. i thk k our calipers are ate calipers anyway.

2.7Lturbo

if you have a manual i would reccommend against super blue... i have no idea why, but it makes the clutch master cylinder squeek sometimes... its so bizzar, hurts nothing but is annoying as all hell!

Just Me

I use ate super 200 in my porsche, since it gets so much track use. for track uss in my S6, which gets stupidly hot ( i posed the numbers earlier last month), i moved up to 600 deg stoptech or motul fluid. Many C5 calipers are ate, the HPs are Lucas. It makes absolutely no difference sine all the fluids are compatible.

In any event, not sure what your point is. The ate is very good fluid, but will absorb water faster than the castrol GT-LMA, and is not even remotely required for street use. So in that respect i feel it is inferior.

For the record the blue is the super 200 gold with blue dye added.

Grant