I have a 2005 E150 van I purchased new and which has been garaged since new. It only goes about 2000 miles a year and has just about 32,000 miles total use. Basically it still looks pretty new.

About 2 years ago I began having brake problems. When going down steep hills while riding the brake (we're talking less than 1/4 mile here) the brake pedal drifts down nearly to the floor. As it gets lower it requires more pressure to push it further, but it still will go almost to the floor. The brakes are still operating during this drift down and I've never lost the brakes when this is happening. Normal driving stops on flat roads etc. have no pedal drift issue. Sitting still though you can slowly push the pedal down to nearly the floor but I'm told this is normal, at least to some extent, due to the anti-lock braking system. In the many years of driving since purchasing the car new I never noticed anything like this. I think it started when one of the rear calipers froze and overheated in the mountains of VT 2 to 3 years ago.

While chasing this problem over the past few years I have done the following:

1) Both rear calipers replaced.
2) Master cylinder replaced.
3) Both front calipers replaced.
4) All rubber hoses in the system replaced.

The brake system has been bled seemingly countless times by multiple mechanics including myself and a mechanic friend working together with a vacuum bleeder, a local garage and a Ford deal using the typical pedal pump method.

I have read that some Ford pickups that are older than my 05 van have a mid-system anti-lock brake valve that needs to be bled but there does not appear to be one of these on my van.

So I'm a bit stumped. My current thinking for throwing more money at it next are:

1) Maybe the new (not a rebuilt unit) master cylinder is bad.
2) Maybe somehow the brake booster is causing the problem.
3) Maybe the anti-lock brake system is somehow causing the problem.
4) Maybe it's a computer issue.

Any thoughts and suggestions would be greatly appreciated. I now have a completely new brake system so am not totally flabbergasted over the $1500 plus I've spent chasing this problem. However it would be nice if the problem could be solved.

Thanks,
BH Davis

 

Did you change out the brake booster as well?

 

No........booster has not been replaced. That is why I'm wondering if it could be the problem. From what I've read online though that isn't likely?
Thanks for lending a hand.
BH

 

Your problem is most likely in the ABS spool valve. Its probably bypassing fluid or it was bleed properly. In order to service bleed these you MUST use the Ford IDS to force ABS pump to run and bleed. If you don't you will have air stuck no matter how hard you try. The less conventional method of this isn't available is what we call the gravel road brake bleed. That's several well placed low speed brake lock up applications causing ABS to activate. This should purge air to the master cylinder.

 

ford390gashog,

My apologies for taking so long to reply to your comments. They are very much appreciated.

I have done as you suggested and did several brake lockups but on a paved road as there were no dirt roads around. I'm assuming this has the same result on the brake system but at a cost to tire wear?

There does seem to be some improvement in the brakes after this test. I'm going to find a dirt road next and give it a real go with slow speed lockups.

Can you tell me what the ABS spool valve looks like and where it is in the system? Since you mention it will bleed air into the master cylinder I'm guessing it's somewhere nearby?

Thanks for helping on this.
BH Davis