Low brake fluid

[deerfarm]

My EX has 10,400 miles. Had it serviced at the dealer at 10,100 miles. It sat in my garage for week while I took a trip. When I used it again, I occasionally got an alarm of "Low brake fluid level". Sure enough, when I checked, it was below the minimum level. I assume that when Ford built the truck they put in the minimum amount and when it sat at cool temps it contracted, thus causing the alarm when I accelerated.

There was not fluid on the garage floor, so I don't think I have a leak.

It was pretty dissappointing that the dealer did not discover this when serviced.

Just wandered if anyone else has experienced this?

 

[Car 54]

That's pretty bad, as brake fluid doesn't compress due to there should be absolutely no water or condensation in the brake fluid. If there is, that's a bigger problem as water content creates air, air creates no brakes pressure.

I'll check mine and post back.

 

[fifthranger]

Could be an isolated incident. I wouldn't worry, but I would add some, and if the light comes on again, you know that there is an issue. If you take the vehicle to the dealer, they will add some fluid and probably forget about it.

 

[boss377]

It was probably down by a couple of cc's all along. Just bring it up to the "max" line on the reservoir, and let it rip.

 

[Car 54]

Oh and low brake fluid isn't necessarily a bad thing, but a leak obviously is. After you add more, go out and press and hold the brake pedal to the floor and make sure the pedal stays firm, then check your level after a quick drive. I'd keep my eye on it for at least a week.

 

[K1200rsport]

Check for the leak, if no leak then it means pads are wearing, check the thickness of the pads.

 

[SWEET ST]

1. Low pads wont cause low fluid, i think that one the master cylinder will show low fluid, also mybe the dealer when serviced they check brakes and bleed them and forgot to replace fluid i would have the check brake system and that should give you a peace of mind !!!

 

[Car 54]

1. Low pads wont cause low fluid, i think that one the master cylinder will show low fluid, also mybe the dealer when serviced they check brakes and bleed them and forgot to replace fluid i would have the check brake system and that should give you a peace of mind !!!

Not quite right, the brake fluid fills the caliper's piston cavity as the pads wear and the piston extends out further as a result, the fluid gets displaced and results in less in the master cylinder.

Usually all four pads completely worn = the min line.

 

[SWEET ST]

CAR 54 WAS BACK IN THE 60'S TODAY'S VEHICLE'S ARE MUCH DIFFERNT AND WITH 10K MILES THE BRAKES ARE MADE TO LAST AT LEAST 18K+ MILES UN LESS U RIDE THE BRAKES, BUT ANY HOW I STILL RECOMENED THAT THE EXPLORER BE TAKEN TO THE DEALER FOR A CHECK UP OF THE BRAKE SYSTEM.


Low Brake Pedal
The brake pedal should be checked for proper adjustment any time a low brake pedal is being diagnosed. The brake pedal is typically adjusted with the master cylinder pushrod. The pushrod is usually (almost always) made of two parts and is lengthened or shortened by adjusting a nut located on the rod. A misadjusted brake pedal may be the cause of a low brake pedal. Drum brakes that are out of adjustment will cause a low brake pedal.

Another culprit is likely to be contaminated, overheated, or aerated brake fluid. This is very common and can not be over looked. Brake fluid is hygroscopic meaning it attracts moisture. If a container of brake fluid is left open it will attract moisture and quickly become contaminated.

The same is true with heat. Heat from the braking system can cause the brake fluid to boil. This causes it to vaporize leaving pockets of vapor in the brake lines. The whole idea of using a fluid like brake fluid is the fact that it is not compressible. On the other hand a vapor like the one caused by overheating the brake fluid is. This vapor in the brake system will definitely result in a low brake pedal.

Brake fluid is rated by the Department of Transportation, the DOT. They rate the different brake fluids by assigning them a number like DOT3, DOT4, and DOT5. The higher the DOT rating the higher boiling point (the more heat it takes to boil). DOT5 brake fluid is silicon based where the other two are glycol based. Never mix the two as this will definitely cause a low brake pedal or at least a loss of performance. This can be remedied by a brake fluid flush. Moisture in a brake system will lower the boiling point as indicated by the chart below.

 

[Car 54]

No need to shout. Adjustable brake pedal, now we're talking old skool.

 

[deerfarm]

Thanks for all of the great input.

As it turns out, the next time I went to the truck there was a small puddle of fluid about a foot behind the left front tire. I took it in today and they said there was a loose connection.

 

[97xxxploder]

i would start it up and have someone hold the pedal to the floor and press as hard as they can as u inspect to see if there is a small leak. small leaks turn to big ones quick!