2005 e150 cold weather brake failure

[BOBMAC]

Greetings and thank you for adding me as a new member.
I have a reoccurring brake problem on my 2005 Ford Club Van that happens only during the winter when temperatures dip below about 15 degrees Fahrenheit.

I will be driving the van for a few minutes without any brake issues.
Suddenly without warning when I want to slow or stop, I find that the brake pedal goes all the way to the floor with no braking ability. Holding the pedal to the floor or pumping the brake causes the abs to pulsate but is no help in stopping the van. After a short time, seconds usually, the pedal returns to its normal height and the brakes work as usual. At no time do any brake warning lights come on the dash. I may go five minutes or 25 minutes without any more brake problems but the brake pedal will suddenly without warning go all the way to the floor again with no stopping ability.

After the last time it happened I called my mechanic from the side of the road (he is very respected and has been in business for over 50 years) and explained the situation. After the pedal returned to normal, He had me hold my foot on the brake pedal to find that the pedal is not spongy and does not slowly sink to the floor. He also had me check the brake fluid to find that the fluid is full and topped off. He said my explanation is not possible.

Again, this only happens on e or twice a year when the temperatures dip below about 15 degrees. Has anyone else experienced this problem?

Thanks,
Bob

[carriedi]

this is a tough one. In most cases when a brake pedal goes to the floor it's a bad master cylinder. In the beginning it will happen but another pump on the brake pedal it would be fine again. after a while it happens more often and sometimes will happen while already at a stop or the pedal will stop the vehicle but slowly creep down and loose the braking that hold the vehicle. Here's a suggestion though, anytime the pedal goes to the floor on a master cylinder that has been in use for a couple of years, it should be replaced. When a master ages there is a build up of sludge builds up in the bore of the master. Under normal braking you clean the bore with every sweep of the seal on the piston. But the portion that doesn't get swept has the sludge. When the pedal goes to the floor the piston seal will get pushed through the part of the bore that doesn't usually get used with the built up sludge. That could affect the seal.

Because of the temperature aspect of the brake problem, you might want to have your brake fluid flushed. Brake fluid is hygroscopic. It attracts water. If you have water in the fluid it's possible that it might freeze in the system. That could valves in the abs or seals anywhere in the system to get held open.

The brake system works on hydraulic pressure. the master is the start of the pressure build up. If the master has a seal that leaks once in a while there will be no pressure build up. something else that can cause a loss of built up pressure is the abs system. The abs will have valves and a pump. that will hold, release and build up pressures in the system. The abs unit can cause a loss of pressure also.

Start with what you can easily do first. If you can find a shop that specializes in brakes they may be more help than a mechanic that does general repair. Brake shops don't have to worry about engines, or charging, or Ac systems. So they usually see more things that can go wrong with braking.

[BOBMAC]

Thank you so much for taking time to post such a detailed response. I wish I could say that I understand brake systems and how they correlate to your suggestions but I myself an illiterate when it comes to auto mechanics. I will certainly share your thoughts with those I turn to for help. Thanks again! Bob

[eurocycles2010]

I have a 2002 ford f 250, when i turn the key on you hear a buzzing noise when started if you apply the brakes and or turn on blinkers the noise goes away, but comes back when you let off brake or turn blinkers off. any help would be great Thank You.

[carriedi]

Need more info...

Hard to say what the noise is or where it is coming from. but just from what you said affects it, I would look at your turn signal flasher.

what you should do is turn the key on but don't start your engine. If it's making noise try to find out where the noise is coming from. Listen for the noise and follow it to where it seems to be coming from. Once you think you are close, use your hand to feel parts to see if you can locate the actual piece that is buzzing. Once you have singled it out, see what it is going to take to remove it. If you can get it out, look for a part number on it. Ford is very good about putting part numbers on almost everything. Google the part number.

[herbivore]

eurocycles2010 wrote:
> I have a 2002 ford f 250, when i turn the key on you hear a buzzing noise
> when started if you apply the brakes and or turn on blinkers the noise goes
> away, but comes back when you let off brake or turn blinkers off. any help
> would be great Thank You.
I have 2004 ford ranger w/ exact same issue
the noise is from the blinker.
the brinker works properly (turn/hazards) except for the noise issue
any luck solving your problems?
thanks!