Grabbing RF brake
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Grabbing RF brake
I have a 78 F250 w/351m w/power brakes, disks in front.
My problem is my RF wheel grabs/locks occassionaly for seemingly no reason w/ only a light touch on the pedal.The problem goes away after several stops, only to reappear the next morning.Pumping the brakes in the morning sometimes helps.Everything checks OK.No one locally can figure it out.Everything is in good condition, clean, well mantained, no leaks.
Any ideas, anyone?
Thanks in advance
Frdtrcklvr
My problem is my RF wheel grabs/locks occassionaly for seemingly no reason w/ only a light touch on the pedal.The problem goes away after several stops, only to reappear the next morning.Pumping the brakes in the morning sometimes helps.Everything checks OK.No one locally can figure it out.Everything is in good condition, clean, well mantained, no leaks.
Any ideas, anyone?
Thanks in advance
Frdtrcklvr
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Joined: Jan 2008
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Welcome to FTE!
Time to get both front wheels in the air to test "pedal to wheel stop" in the front braking system.
One person turns the wheel while the other applies the brake lightly.
Compare the two.
Look for leaking brake fluid on both rotors.
Once you reply,this thread will be moved to the Brakes related forum.
Time to get both front wheels in the air to test "pedal to wheel stop" in the front braking system.
One person turns the wheel while the other applies the brake lightly.
Compare the two.
Look for leaking brake fluid on both rotors.
Once you reply,this thread will be moved to the Brakes related forum.
Logistics Pro
Joined: Jan 2001
Posts: 3,740
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From: Central NYS
Originally Posted by frdtrcklvr
I have a 78 F250 w/351m w/power brakes, disks in front.
My problem is my RF wheel grabs/locks occassionaly for seemingly no reason w/ only a light touch on the pedal.Frdtrcklvr
My problem is my RF wheel grabs/locks occassionaly for seemingly no reason w/ only a light touch on the pedal.Frdtrcklvr
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grabbing brakes
No, I have not changed the hoses, but I will now!
I am a refrigeration/A/C serviceman, and I have had hoses delaminate exactly the way you describe.It never crossed my mind, however about the brakes.
Thanks for the Idea!I will change the hoses as soon as I can.
Thanks.
FTE is fantastic!
Frdtrcklvr
I am a refrigeration/A/C serviceman, and I have had hoses delaminate exactly the way you describe.It never crossed my mind, however about the brakes.
Thanks for the Idea!I will change the hoses as soon as I can.
Thanks.
FTE is fantastic!
Frdtrcklvr
Posting Guru
Joined: Jul 2001
Posts: 1,613
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From: Gainesville, FL
All,
Flex hose failure is common for these old beast. But not likely the failure mode you are describing. When a hose seizes, it generally gets worse as the vehilcle warms up.
Generally, it is almost impossible for front brakes to pull unless:
1. There is a leak in one of the rear brakes. This would eventually show up at the reservoir. No leaking has been seen?
2. Caliper drag. Probably not your problem either. This would show premature pad wear on the suspect side. Strangely enough, the dragging caliper is not nessessaryly the side the vehicle drags to.
3. Warped rotor. This could cause a pull but, it would also cause a pulsing of the brake pedal and, when bad enough, a shaking of the steering wheel.
4. What if something is leaking on to your rotor? Once you have warmed the brakes up and burned off the suspect product the brakes work fine? Here is my best guess: You have a inside grease seal that is leaking. The vehicle warms up and the grease melts. The spinning wheel throws the grease clear. After you stop the grease leaks onto the rotor. The breaks cool and the grease hardens. You start her up and down the road you go. You apply the breaks but the greased side slips and the other side grabs. Your truck pulls.
It's really that simple,
KingFisher
Flex hose failure is common for these old beast. But not likely the failure mode you are describing. When a hose seizes, it generally gets worse as the vehilcle warms up.
Generally, it is almost impossible for front brakes to pull unless:
1. There is a leak in one of the rear brakes. This would eventually show up at the reservoir. No leaking has been seen?
2. Caliper drag. Probably not your problem either. This would show premature pad wear on the suspect side. Strangely enough, the dragging caliper is not nessessaryly the side the vehicle drags to.
3. Warped rotor. This could cause a pull but, it would also cause a pulsing of the brake pedal and, when bad enough, a shaking of the steering wheel.
4. What if something is leaking on to your rotor? Once you have warmed the brakes up and burned off the suspect product the brakes work fine? Here is my best guess: You have a inside grease seal that is leaking. The vehicle warms up and the grease melts. The spinning wheel throws the grease clear. After you stop the grease leaks onto the rotor. The breaks cool and the grease hardens. You start her up and down the road you go. You apply the breaks but the greased side slips and the other side grabs. Your truck pulls.
It's really that simple,
KingFisher
Senior User
Joined: Jun 2004
Posts: 113
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I had this same problem on an aerostar. We would be driving along and the brake would just lock up under normal use. the only way to unlock it was to "slam" them really hard once or twice. end-ed up replacing calipers and hoses to fix it.
