02 anti lock brake problem

[DAVEQ]

When stopping the anti lock brakes are activating when the speedo hits 7-8 mph or below . Truck pulls to the left like the right front is releasing . This has been going on for a week or so since I had to really stand on the brakes to avoid hitting a deer in the road . No brake or anti lock brake lights on the dash are lit up , the brakes work fine until slowing , soon as I slow to 7-8 mph the anti locks kick in . Any thoughts ? , thanks in advance .

[maxwedge]

Get it scanned on an abs function scanner and they will see which wheel sensor drops out before the others, causing this problem.

[sreve]

call the chevy dealer nearest you. there is a tsb on it that pertains to your truck and this problem. abs sensors are cleaned and or replaced. they recalled the full size trucks back to '99. there may be a free fix for you.

here's some copy\paste

Brakes and Traction Control: All Technical Service Bulletins Brakes - Low Speed (Below 5 MPH) ABS Activation Bulletin No.: 02-05-25-006B Date: January 05, 2006 TECHNICAL Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting Surface) Models: 1999-2000 Cadillac Escalade 1995-1999 Chevrolet Silverado (Old Style) 1995-2000 Chevrolet Suburban, Tahoe (Old Style) 1995-2003 Chevrolet Astro Van, Blazer, S10 1995-1999 GMC Sierra (Old Style) 1995-2000 GMC Yukon, Yukon XL (Old Style) 1995-2001 GMC Envoy, Jimmy 1995-2003 GMC Safari Van, Sonoma 1995-2001 Oldsmobile Bravada Supercede: This bulletin is being revised to update the correction and warranty information. Please discard Corporate Bulletin Number 02-05-25-006A (Section 05 - Brakes). Condition Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph). Upon investigation, the technician will find no
set. Cause The cause of this condition may be an increased air gap between the wheel speed sensor and the hub reluctor ring due to rust and debris built up
sensor mounting surface. Correction Measure AC voltage and clean wheel speed sensor mounting surfaces. 1. Raise the vehicle on a hoist. 2. Disconnect both the front wheel speed sensor harness connectors. 3. Place a DVM across the terminals of each sensor connector. 4. Rotate the wheel with hand speed and measure the ACmV's. The reading should be at least 350 ACmV's. 5. If the reading is between 200 and 350 ACmV's, remove the wheel, caliper and rotor in order to gain access to the speed sensor. 6. Remove the wheel speed sensor and plug the hole to prevent debris from falling into the hub during service. 7. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery cloth, ScotchBrite(TM) or other suitable material.
to thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion. 8. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up or other causes. Check the mounting surface
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3) positions/directions. If the sensor head is distorted, replace the sensor. 9. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant, P/N 89022217 (Canadian P/N 89022218).
10. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing grease to the hub surface and sensor 0-ring prior to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (Canadian P/N 993037). 11. Install either the original sensor or a new one in the hub and secure the sensor. Ensure that the sensor is seated flush against the hub. 12. Install the rotor, the caliper and the wheel. 13. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel by hand. The voltage should now read at least 350 ACmV's.

[DAVEQ]

Thank you very much .

[bowtieboy12]

had this happen, you get on the brakes and it just grinds and you literally hafta satand on the pedal to stop...easy fix, pull the ABS fuse. you dont need ABS anyway if you can drive

[bighogtoy]

Originally Posted by DAVEQ

When stopping the anti lock brakes are activating when the speedo hits 7-8 mph or below . Truck pulls to the left like the right front is releasing . This has been going on for a week or so since I had to really stand on the brakes to avoid hitting a deer in the road . No brake or anti lock brake lights on the dash are lit up , the brakes work fine until slowing , soon as I slow to 7-8 mph the anti locks kick in . Any thoughts ? , thanks in advance .

My friend I (had) the same problem with my truck let me tell you it drove me nuts not including almost running into others cars at almost no speed same like your problem.
But any way I went and purchased a used complete (used) ABS module (no luck) went and purchased two (front L/R ABS sensors and again (no luck) but the answer war very simple you may not believe this but there is just ehgnoth rust build up on the mating surface of the front L/R wheel hub where the sensor mounts to the hub that litter rust will cause or push the sensor up causing the AC voltage to the sensor not to be consistent.
You will need to remove the sensor, then cover the sensor hole with paper towel and file the rust down on the hub to be flat and clean please be very careful no tot drop any rust inside the sensor hole (very important).
That should clear your problem if you need any more help please feel free to e-mail me at old_toy1@hotmail.com.
Good luck.

[ericn1300]

don't even f*$# with it, it's a hidden warranty item that was announced in a recall by GM only in the "rust zone" of the US. Wisconson had to sue to be included in the recall and in a consent decree GM agreed that all vehicles exhibiting the same problem would be fixed by the dealers at no charge nationwide. NHTSA has a bulletin on it on their website.

[aldo19311982]

thank you all 4 ur feedback i was lookin towards sensors as well i asked the friend with this problem but i should have asked a few more like when does it happen low high all the time . seems speed does make a difference. thank u all. Dave. ps if i can shed some light on ur problems feel free to ask . ive been a tech 4 40 yrs and have a variety of knoledge hope i can assit.