dreamcar2012

Hello,
Should I have a break fluid flush done on my 2010 A4? it has around 49k miles, I bought it a little over a yr ago, and wondering in reality how often this needs to get done.
Thanks in advance!

uberwgn

Being in a humid environment, you should be adhering to the 24 mos change cycle, Dreamer.

dreamcar2012

will do! thanks.....dealer in my area charging me $99 is that a good price?

Redd

You can probably get it done at Sears or other large chains or dealerships for half of that.

The rule of thumb for normal brake fluid is to change every two years BUT it is now possible and simple to actually TEST the brake fluid instead of just throwing it out and buying new fluid all the time.

Check out Amazon, there are pen-sized testers that measure the specific gravity of the fluid, and the moisture content. Two $25 tools and in theory a brake shop or dealer is supposed to measure the moisture content and tell you "Naw, it doesn't need a change" if it doesn't need one yet. Of course, they'll still charge you for 1/2 hour of labor, catch-22, so they just flush on schedule.

Open fluid reservoir, poke in tester, read tester. Sixty seconds and you can check every six months, your tool will last fifty years.

uberwgn

Dreamer, if you can't hanlde it yourself, that price is more than fair!

ArronBurns

Your brake fluid should be flushed every 2 years. Its not a service I would skip as brake hydraulic repairs can be very expensive. You can find more information here. http://themechanicswrench.com/brake-...-stopping-you/

dreamcar2012

thanks everyone! have a wonderful day

Moviela

The moisture in brake fluid is a measure of where you live (Florida or Nevada for example) but has little effect on braking. Since the '20's cars have used glycol based brake fluid, and the moisture content is not a contributing factor to corrosion in the brake system. When you think about it, how much moisture can enter the system through the tiny vent hole? Not much I assure you.

So why is almost every car maker insisting on changing the brake fluid every two years? It is from copper absorption. The copper is in the brazing material used to manufacture the steel brake lines. As the additive inhibitor in the brake fluid is depleted, copper ions are absorbed into the fluid and acts as an oxidizer when it comes into contact with iron or steel. This can cause considerable corrosion to very expensive ABS parts.

You can use test strips to measure the copper, but adhering to the two year change interval (from date of production) will keep you out of the woods.

http://www.nist.gov/manuscript-publi...?pub_id=852905

Redd

Actually car makers vary widely in their brake fluid change advice. Some claim it is a "lifetime fill". Copper in brake lines? No, copper tubing is not suitable for hydraulic lines so that should not be an issue. (Copper work hardens under repeated stress, and then splits and fails. Not suitable for hydraulic lines.)

But if you've ever had to rebuild a brake wheel piston cyclinder because it was internally rusted and leaky--that's water damage. A car that is seaside used to take that damage in only four years. The metals are more corrosion resistant today, but the water still accumulates.

The water also superheats and flashes into steam, causing brake failure during hard long braking. Copper is nothing to do with it. All the fluid manufacturers warn against brake failure from moisture accumulation. Both from corrosion, and steam.

Copper ions? Where's the copper going to come from, tourists throwing pennies in the brake fluid fountain?

Moviela

I guess you are not aware of the process used to manufacture steel brake lines. It involves copper. The copper gives up an electron to become a copper ion in the brake fluid as the inhibitor is depleted. The copper ion then finds an electron in the iron in the system, thus oxidizing the iron. It is "rusted,"
but not from water. Any water is actually inhibited from oxidizing in the braking by the glycol
based fluid.

Your coolant is also glycol based, and is mixed with 50% water, and does not corrode engines.

Excessive water in the brakes can cause it to boil, but that is an unusual condition not encountered by a properly maintained system. Living at the beach has no effect on the internal parts of the brake system, although some tolerable corrosion may appear on external surfaces.

By the way, modern pennies are only 2.5% copper, and should be fine in your brake fluid fountain as long as you change it every two years.