F350 spongy pedal after caliper / hose replace.

[Roy French]

After a routine replacement of the right front caliper and brake hose on my Dads 2007 F350, we had a spongy pedal. The job went quickly and the master cylinder was never even close to running dry. The brakes bleed out to a rock hard pedal with the engine not started. After starting the pedal would slowly go to the floor to the point of the idle being affected by the hydroboost unit. The truck would stop and even lock the wheels, but the pedal just didn’t feel the same. We read on different Ford forums that other people have had this issue, spending a ton of money throwing parts at the problem. In this case the fix was to run the abs bleed sequence on the scanner. We then re-bleed at each wheel. The only bleeder to pass air was the right front. Only a small amount came out, like two little bubbles. It must have been in the abs unit, in a spot that would not bleed out without running the pump. His pedal is back to normal now, allowing him to tow their 5th wheel back to Florida for the winter.

Topic

[dreamer2355]

Thanks for the info and yes, most newer vehicles with ABS require a bi-directional scan tool to bleed the braking system.

[Roy French]

Hey Dreamer,
I have had the brake lines open on lots of vehicles with abs and never ran into this before. A 2003 chevy van I was working on, bleed out with no trouble recently for example. Is it only certain vehicles or am I just getting lucky?

[Jacob Andersen]

Hi, I had similar problems when replacing and overhauling brakes and calipers on all four wheels.

I have described my experience in this forum – and a part of my problem might have been trapped air in the ABS-system. But I am some 2 hours from a work shop with VW scan tool so I just used “poor mans VAG-COM (VW scan tool)” AKA driving like crazy getting the ABS-system to kick in.

But very nice that You managed to solve the problem. Brakes can indeed be annoying, but I suppose they are good to have around.

[Roy French]

Hi Norsology. This is a heavy 6 wheel truck, so it’s hard to drive it like crazy. We did try locking the brakes, making the abs run. We also tried just unplugging the abs module. Nothing brought the pedal back like running the abs bleed procedure did. I’m glad it worked for you. I think I remember Eric doing that on some Honda he was repairing.

[dreamer2355]

I have also worked on many vehicles where i have been lucky in bleeding a ABS system without the aid of a scan tool. But there is always that ‘one’ that comes onto the shop where i am having to reach for the scanner.

[stingray66]

I used to have problems tillI got a motion power bleeder for some reason that seems to work out good with the abs system

[Author]

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