Brake flutterijng

[whmstang99]

My 2003 Sport trac today, when I got on the brake, it slowed down then almost like I was on ice slip the pedal went down and it sounded like a grinding noice. zIt stopped, it wasn't like I lost control, but part of it felt like the ABS engaged, but part felt like metal on metal. I checked the pads and rotors, and they look good. I topped of the master cylinder, and drove it again. It inially did it then it seemed to get better. For the next 15-20 minutes it was fine. I will see in the morning when it is cool if it goes back
I thought maybe the ABS unit, then thought maybe master cylinder, any thoughts.

Art

 

[08v6]

I Have The Same Problem, But It Happeneds Like Once Or Twice A Week, It Was Fine When I First Got The Truck But As Soon As I Started Wheelin, The ABS Light Went On, I Didnt Think AnyThing Of It Cause That Light Turnes On Just From The Light Sand In The Pits I Go To, But It Hasnt Shut off In Like A month, And My brakes Are Doing The Same As Yours On A Regular Basis, It Is Kinda Creepy, Cause At First It Feels Like You have No Brakes Then THe ABS Pump Starts Going, I Just Release The Brakes And Step On Them Again And It Fine, But I Would Like To Know What The Problem Is As Well

 

[whmstang99]

sport trac brake fluttering

I am guesssing it is either abs unit, master cylinder, or abs sensor but I am old school so I know nothinG about abs

 

[charli]

ABS is seldom tested by drivers. When under hard braking, if any wheel speed slows more tham the others the ABS computer detects it and pulses that wheel so as not to loose traction. This process can be alarming if you have never tested your ABS before. Having a different size tire from the others can also cause the ABS to activate.
The ABS light should illuminate when the system is active and you may hear grinding noise and pedal vibration. Try hard braking with two tires in grass ant two on pavement (slow about 25-30 mph).
This will activate ABS. Make sure you are at a place where there are no vehicles or persons near to avoid problems. The reaction can surprize you.

 

[08v6]

K I Am Not Sure About WHMstang99s Problem, But I Can Say My ABS Problem Is Not Normal, It Happeneds Under Normal Braking And Right When The Trucks About To Stop Thats When It Happeneds, I Will Start braking As I Approach A Light And Its Fine...Its Slows And Slows And Slows Just Fine....Then Right When Its About To Stop. It Kicks In And The brakes Flutter And The Truck Rolls Like Another 5ft. Like I Said I Just Pump It Once And It Goes Away.

 

[whmstang99]

Brake fluttering

Yea, that is more percise of what my Sport Trac does. I did some research and appearently it is a problem that a lot of vehicles have. They say it can be as simple as brake dust from Metalic pads on the hub sensors for the ABS to more expensive such as needing new hub sensors or worse a new ABS system. Now the other thing I hear is that if you have a 4x4 like I do, then it won't be dust since they say the hubs are sealed, which means if this is true I am seeing big bucks.

 

[whmstang99]

ABS brake

I am now hearing that you can unplug the ABS and drive old school brakes?

 

[08v6]

REally? Where Did You Hear This? And How Do We Do It? I hate ABS, I Dont Have It In My Stang And I Dont Want it In Any Of My Cars.

 

[charli]

When ever you disconect any sensor an a vehicle with computer control, be careful, you may also disable other related systems. It is better to repair the system than disable it. ABS can be a life saver when working properly. I suggest carefully inspecting the components. Are there any diagnostic codes present? Check master fluid level. Has the hydraulic fluid ever been replaced? Are there any leaks at the wheel cylinders? Check that there is no play in the wheel bearings. With the wheels off, check that all the tires are the same diameter, see if there is rust on the rotors, check the pads, inboard and outboard for wear, check the wheelspeed sensors (rust or foreign material on sensor or hub can cause erroneous readings by the computer), make sure the sensor connections are not corroded or have bad wiring.