ABS kicking in at slow speed

[Mark Heisser]

So I changed my rotors out and put on new pads about 2 wks ago,bled the brakes and ever since the ABS kicks in at very slow speeds.Pulled the wheel sensors and cleaned them.I dont have any ABS light on or nothing,let go of the steering wheel and it doesnt pull to 1 side or nothing just goes straight.Could the new rotors have a different toner ring than the old ones.I threw away the old rotors so I cant compare.Its never done this till the new rotors were installed any help is appreciated

 

[Richard L]

You probably have the wrong rotors. The rotors contain a tone-ring that the ABS sensor uses to determine the speed of rotation of each wheel. The new rotors probably have a tone-ring, but not the right tone-ring, the spacing of the tone-ring segments are different. I think you may have rotors from an Explorer or a different model Sport Trac??? perhaps for a 4X4?



Many parts stores list the Sport Trac rotors as being interchangeable with other earlier model Explorers, but that is not true, as many other here have found out about 10 years ago. Sport Trac came with 12" rotors while early Explorers had 11.5" rotors...land a different Tone-Ring.



The other possibility is that you may have knocked the sensor out of position and it is not picking up the signal from the tone-ring, or you have a bad sensor connection (unplugged or broken wire) but I would think a bad sensor connection would give an ABS warning light?



...Rich

 

[Mark Heisser]

Thanks for the info thats what I think it is too since it started immediately after new rotor installation

 

[Yardsale]

Agree with Rich that you were given the wrong part.



Just a suggestion - keep your old parts until after a satisfactory test period. I put them in a box for a week or so, then toss 'em.

 

[swshawaii]

Sport Trac came with 12" rotors while early Explorers had 11.5" rotors...land a different Tone-Ring.

Good point Rich. Any way of measuring the rotors? NAPA only shows ONE rotor/hub replacement. Why no ABS light? Faulty caliper with no pull?

 

[Yardsale]

Tape measure?

 

[Jake Connor]

When younger and cars simpler I did a lot of my own work. @75 I have a mechanic do most work. Have a 2003, low millage Sport Trac 4X4 XLT 4.0 SOHC V6. Had rotors and pads replaced two yrs. ago. Now developed a problem, where, when I come to a slow stop I get a gushing & clicking sound. Pedal drops inch or so. Scary, wondering if I am going to stop. Mechanic checked sensors, toner ring and everything else he can think of. No codes No ABS light. It's mentioned, here, of wrong parts. Don't know if there is any comparison to discussion here. If so shouldn't it have shown up before no. Any ideas would be appreciated.

 

[Richard L]

Jake,

I'm just taking a wild guess here, but I think you need to have your mechanic check out the power brake booster.



...Rich

 

[Jake Connor]

Thanks Rich. I'll mention that to him.