brake pedal woes
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From: Upstate NY
brake pedal woes
I don't know whats up with my new truck, its a 04 f250 scsb, 4x4, 5.4l with 61k orig miles on it.
truck will stop on a dime, has NO pedal sinking, but it takes about 3/4 of the pedals travel to apply pressure to the pads and have the truck stop, sometimes if I push the pedal down then let up and push it again the pedal wont travel as far, I just flushed the system today, no air in the lines, is there a bleeder on the abs? truck has 4 wheel abs
not sure whats going on here, if anyone can comment that would be great
truck will stop on a dime, has NO pedal sinking, but it takes about 3/4 of the pedals travel to apply pressure to the pads and have the truck stop, sometimes if I push the pedal down then let up and push it again the pedal wont travel as far, I just flushed the system today, no air in the lines, is there a bleeder on the abs? truck has 4 wheel abs
not sure whats going on here, if anyone can comment that would be great
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Joined: Apr 2012
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From: Spanaway
Hydra-boost system ? If yes maybe you need to flush the power steering
fluid to freshen up the fluid and clean out any junk. The other thought I
had was a problem with the master cylinder leaking a bit back into the
reservoir.
Sean
fluid to freshen up the fluid and clean out any junk. The other thought I
had was a problem with the master cylinder leaking a bit back into the
reservoir.
Sean
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From: laporte in
It shouldn't be hydra-boost since its not diesel.
Bleed the crap out of em. Start at passenger rear. Bleed it 5 times. Repeat at every wheel after that from LR, RF, and LF. That's how I got air out on my 05 after flush change
Bleed the crap out of em. Start at passenger rear. Bleed it 5 times. Repeat at every wheel after that from LR, RF, and LF. That's how I got air out on my 05 after flush change
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From: Jersey Shore Not Seaside!
Typically air in the ABS. If there is any in the controller valves, pump, accumulator the only way to get it out is to exercise the system. Ford's scanner can do that readily; you can do that by taking the vehicle out on a slippery surface and doing a few stops at 25-30 mph to activate all three channels and drive air into the piping, then re-bleed. You may have to do ABS stops with a full bleed several times to get out all the air. We used to have to do this when building up a prototype brake system and there was no software to activate the controller.
The other situation is if one sliding pin on a caliper is frozen causing a caliper to twist while braking.
The other situation is if one sliding pin on a caliper is frozen causing a caliper to twist while braking.
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From: Upstate NY
Typically air in the ABS. If there is any in the controller valves, pump, accumulator the only way to get it out is to exercise the system. Ford's scanner can do that readily; you can do that by taking the vehicle out on a slippery surface and doing a few stops at 25-30 mph to activate all three channels and drive air into the piping, then re-bleed. You may have to do ABS stops with a full bleed several times to get out all the air. We used to have to do this when building up a prototype brake system and there was no software to activate the controller.
The other situation is if one sliding pin on a caliper is frozen causing a caliper to twist while braking.
The other situation is if one sliding pin on a caliper is frozen causing a caliper to twist while braking.
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From: Jersey Shore Not Seaside!
You don't have to pull everything apart. Go behind each caliper, loosen them one or two at a time by 1/4" and push on them to see if the pins move in and out easily. The bottom front pins may have resistance on the '99 to'04 versions due to the rubber bushing. Just make sure when you snug them back up that the flange of the pin fits properly into the caliper.
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From: Upstate NY
will do, currently I am doing the mod where you turn out the rod on the booster, I have bled the brakes and there is no air, when I removed my master cylinder there was no o ring between the master and booster isnt there supposed to be?
I will check the slides after this, just dont want to hook master up and find a vacuum leak
I will check the slides after this, just dont want to hook master up and find a vacuum leak
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From: Spanaway
Sean
P.S. That will teach me to
& 
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From: Jersey Shore Not Seaside!
There does not need to be an O-Ring between the M/C and booster.
The booster rod adjustment is not a "mod" and if you are not careful in setting it you will have brakes that don't release. All M/Cs are supposed to machined to a depth spec for the pushrod. Some aftermarket companies have poor quality control and therefore sometimes it's is need to be re-adjusted.
The booster rod adjustment is not a "mod" and if you are not careful in setting it you will have brakes that don't release. All M/Cs are supposed to machined to a depth spec for the pushrod. Some aftermarket companies have poor quality control and therefore sometimes it's is need to be re-adjusted.
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From: Upstate NY
yeah I did adjust the rod today, pedal is much better, still feels like there may be air in the system, but pedal will not sink to the floor, just going to leave it the way it is
gotta put some new rear pads on too
also I checked drag on the wheels and there was none
gotta put some new rear pads on too
also I checked drag on the wheels and there was none
Lead Driver
Joined: May 2003
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From: Lyndonville, Vermont
Do a complete caliper and brake pad check. Check hoses for blow outs..Have someone check the hoses while you stand on the brakes.
If you can let up and the pedal is a little better its usually a caliper or pin or pad. Not air.
Years ago it used to be the rear drum brake adjustment that would give the same symptoms.
Dick
If you can let up and the pedal is a little better its usually a caliper or pin or pad. Not air.
Years ago it used to be the rear drum brake adjustment that would give the same symptoms.
Dick
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From: Upstate NY
Thanks Dick
I know the inside pads on the rear are pretty worn, I think im going to do new rear pads tomorrow after I go hunting, I know everything on the rear is original with 61k on it
I know the inside pads on the rear are pretty worn, I think im going to do new rear pads tomorrow after I go hunting, I know everything on the rear is original with 61k on it
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From: Upstate NY
alright rear pads needed replacement, new pads are on rear, slide pins greased also.
initial pedal is MUCH better, but I can still get brake pressure at a taller height if I pump it a second time.
So I suppose the next step is to get a helper to stand on the pedal with the truck running while I grab the hydraulic brake hoses to see if any are bulging, I'm also going to check the passenger front brake caliper to see if the pistons might be siezed, under hard braking the truck turns left
initial pedal is MUCH better, but I can still get brake pressure at a taller height if I pump it a second time.
So I suppose the next step is to get a helper to stand on the pedal with the truck running while I grab the hydraulic brake hoses to see if any are bulging, I'm also going to check the passenger front brake caliper to see if the pistons might be siezed, under hard braking the truck turns left
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From: Stephensville WI
Weak or ballooning hoses will not cause your pedal to pump up to a taller height. That is a sign of air still in the system.
A bad flexible hose will cause your pedal to fall as you hold the truck stationary, like at a red light.
A bad flexible hose will cause your pedal to fall as you hold the truck stationary, like at a red light.