2001 Ford Expedition Losing brake pedal pressure

Tiny
MGRIZER
  • MEMBER
  • 2001 FORD EXPEDITION
  • 5.4L
  • V8
  • 4WD
  • AUTOMATIC
  • 220,000 MILES
Brake pedal seems to be engaging a little lower than normal. Truck stops fine however if at a stop light the pedal slowly starts to drop and the truck creeps forward unless you apply additional pressure on the pedal. Fluid level is good and has not dropped

I have:
Replaced the MC (rebuilt from OReilly)
Bled the brakes several times (new fluid coming out in solid stream)
Checked for leaks at the wheels (none noticed)
Checked the vacuum line to the booster (good vacuum)
Checked the one way valve on the booster (only allows single flow)
Just replaced rear pads (even though old pads were at 25%

With the truck off the pedal pumps up hard. But will slowly lower with constant pressure on the pedal. If I start the truck after pumping it up the pedal drops quickly

Do you
have the same problem?
Yes
No
Saturday, November 14th, 2015 AT 6:57 AM

3 Replies

Tiny
HMAC300
  • EXPERT
This may be an abs unit problem. Either the accumulators are bad or in bad shape or the system needs bleeding with a scanner to open everything up inside abs. It probably still has air in it if scanner bleed fixes problem. These can be rebuilt.
Was this
answer
helpful?
Yes
No
Saturday, November 14th, 2015 AT 7:17 AM
Tiny
MGRIZER
  • MEMBER
So this would need to be taken to a dealer or shop that has the correct machinery to bleed the system with the abs system open?
Was this
answer
helpful?
Yes
No
Saturday, November 14th, 2015 AT 7:30 AM
Tiny
HMAC300
  • EXPERT
Yes any garage that has a pro scanner can do this.
Was this
answer
helpful?
Yes
No
Saturday, November 14th, 2015 AT 7:53 AM

Please login or register to post a reply.

Recommended Guides