Change Brake Fluid at 30,000 Miles?

Took our 2014 Touring CX-5 to the dealer to have the 30,000 mile service done. All good but they say that the brake fluid is starting to discolor...orangish in color. They recommended replacing the fluid at a cost of $150.00+ USD. I declined.

Does brake fluid really "go bad" after only 30,000 miles? We're in S Texas where the summers are pretty brutal so maybe the Mazda brake fluid is breaking down in the heat? Or the dealer just wants to sell a service that seems to me like it would be fairly profitable?
Just curious...
Bill
 
Brake fluid should be changed approx every 2 years. It is hydroscopic (absorbs moisture) and once it has enough moisture in it, can boil and become ineffective.

Doesn't matter what car manufacturer, the brake fluid all has the same characteristics.

$150 to change it sounds over the top, though. Should be far less than that.
 
Another problem with getting moisture in the fluid is that it can damage the inside of the ABS pump which is packed with ultra fine tolerance metal parts and would be very expensive to replace.

I buy my brake fluid from Walmart and a big 1qt bottle is about $4 so your guys are looking to charge $146 labour. Keep in mind that the reservoir hold about half quart ( sorry, we talk litres over here) and the system will hold the rest. Being a time served mechanic I do my own and usually end up with a bit left in one of those big bottles. The reason I am saying this is because I once bought my fluid from a dealer who wanted to sell me one of those small bottles as "that's all they used". That told me they were only purging the reservoir - it needs a big bottle. I would go to a reputable local garage and ask them to do it.
 
Brake fluid should be changed approx every 2 years. It is hydroscopic (absorbs moisture) and once it has enough moisture in it, can boil and become ineffective.

Doesn't matter what car manufacturer, the brake fluid all has the same characteristics.

$150 to change it sounds over the top, though. Should be far less than that.

Hygroscopic is the word you want to use in this instance. Other than that you and Anchorman are correct.
 
Interesting that changing brake fluid isn't shown in the maintenance schedule. I know that bake in the 80s that the recommendation was to change/flush the brake fluid every 2-3 years. I normally bleed the system after a brake job. Could we be hanging on to an old idea too long? Ed
 
Interesting that changing brake fluid isn't shown in the maintenance schedule. I know that bake in the 80s that the recommendation was to change/flush the brake fluid every 2-3 years. I normally bleed the system after a brake job. Could we be hanging on to an old idea too long? Ed
Was thinking the same in regards to the maintenance schedule. Neither is changing the trans fluid, but people are so dead set against it, but regular brake fluid changes are a good idea? I'm NOT arguing against it, probably a good idea seeing how important brakes are. I think 30k miles is a bit too soon, $150 is a bit much, considering they'll probably pressure bleed these things and it won't take them long at all. I, personally, have never bled an entire system all at once. Just when I changed out a brake caliper or wheel cylinder usually after many years or thousands of miles of use. But with the modern ABS systems and EBFD systems, probably not a bad idea to get into a regular service interval.
I just wonder why a system as important as this doesn't get on the maintenance schedule as far as the fluid is concerned, say every 50k miles or so.
 
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Interesting how Mazda recommends replacing brake fluid @24 months or 40k km in Mexico, but has no such recommendation for the US.
 
Hygroscopic is the word you want to use in this instance. Other than that you and Anchorman are correct.

The 2012 VW Jetta that I just sold back to VW had a recommended 2 year change interval for the brake fluid. Also had a 40k mile interval for the transmission fluid.
 
Interesting how Mazda recommends replacing brake fluid @24 months or 40k km in Mexico, but has no such recommendation for the US.

All my vehicles, including my motorcycle, get the brakes flushed and bled every two years.
 
I say 4 years. get a friend to pump the brakes, some 3/16" urethane hose, and a qt of wally dot3 30mins ... done!
 
I need to change mine out as well. Just need to find the time to be bothered with playing with the mitivac
 
Its not 4 years any more. These modern systems have hugely complicated ABS pumps with superfine tolerances and they are lubricated by clean fluid. All the UK models have a 2 year schedule according to Mazda. See attached.
 
Two years makes sense in light of the tolerances and water absorption over time. Found a Firestone shop that will do the brake fluid flush and fill for about $80.00 USD. Almost half what the dealer wanted. Guess I'll have the fluid changed to be safe.
Thx for all of the responses!
Bill
 
ok, how about 2 to 4 years? lol Hey, thats better then about 97 out of 100 CX5s 97% (yea thats a guess) get fresh fluid ONLY when a caliper piston wont retract from corrosion or some other form of corrosion failure. I like the 4 years on coolant and brake fluid. My brother went 12 years on his chevy truck, was $1500 to replace dang near everything. Only had 68,000 on it. If he would have bled his brakes more often, his calipers and wheel cyls would still be working fine. But sadly, thats how 97% of the people maintain their vehicles. $80 sounds pretty fair.
 
Just brought mine to dealer for 30000 also and they said the same that my fluid is dirty and needs to be replaced. I'm plainning on waiting for summer and I will just bleed it out through one caliper and refill the reservoir.

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Ok because I'm going to put higher boiling point fluid in when I flush mine. I may just let the dealer do it for convenience with my supplied fluid
 
Just brought mine to dealer for 30000 also and they said the same that my fluid is dirty and needs to be replaced. I'm plainning on waiting for summer and I will just bleed it out through one caliper and refill the reservoir.

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The old school way is bleed the farthest caliper (wheel cylinder on drum brakes) from the master reservoir . then the other three working your way closer. But I think it was on a honda element, I actually read the manual and it was some different method/order. But if you haven't cracked any brake lines or replaced any parts, and are bleeding just for fluid replacement, dont think it matters the order so much. But you want to see clean fluid coming out of each brake. clean fluid in each caliper is kinda the end goal of the fluid replacement. I use a $4 turkey baster and suck all the brown fluid out of the res and add clean, then bleed manually with the assistance of a helper. power bleeders are better, but never used one. maybe thats why I say every 4 years! lol
 
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