First let me say THANKS for a great site. It has helped me over and over again. This is the first time I needed to ask after searching for a while.

Now to the problem.

Every time I come to a stop the ABS kicks in at low speed (10-15mph) even on perfectly clean blacktop. The truck does stop but gets a little scary. I already replaced the sensor over the rear and I can't find anything wrong with the fronts. This all started because the ABS light was on and I replaced the sensor. There were no problems with braking prior to me changing the sensor. I disconnected the sensor and now the brakes are fine (ABS disabled). I really don't want to leave it this way, I'm coming up on inspection.

Can a difference in tire wear cause this? Thank you in advance for your help.

Tom

 

Now I know this is giving me a headache, the truck is a '99, not a '97. Sorry for the typo.

Tom

 

Here's an excerpt from the service manual for your symptom. Lots of possible causes.


o ABS misfire, ABS too sensitive, ABS fires on normal stop

Possible Source(s):
§ Rear anti-lock brake sensor indicator.

Action(s) to take:
§ REMOVE the rear sensor from the differential housing; INSPECT rear anti-lock brake sensor indicator.

Possible Source(s):
§ Front anti-lock brake sensor indicator(s).

Action(s) to take:
§ INSPECT for damaged teeth. INSPECT both front anti-lock brake sensor indicator(s).

Possible Source(s):
§ Sensor output.

Action(s) to take:
§ If left front anti-lock brake sensor output is out of sync, GO to «Pinpoint Test F». If right front anti-lock brake sensor output is out of sync, GO to «Pinpoint Test H». If rear anti-lock brake sensor output is out of sync, GO to «Pinpoint Test J».

Possible Source(s):
§ Sensor circuitry.

Action(s) to take:
§ GO to Intermittent Failures to test circuits 514 (YE/RD), 516 (YE/BK), 521 (TN/OG), 522 (TN/BK), 523 (RD/PK) and 519 (LG/BK).

Possible Source(s):
§ Wire insulation.

Action(s) to take:
§ INSPECT the wiring harness from the front anti-lock brake sensor knuckle to the frame and from the rear axle to the frame for worn or chafed wire insulation.

Possible Source(s):
§ Rear brake adjustment.
§ Linings.

Action(s) to take:
§ ELIMINATE the base brake system as the cause of the problem.

Possible Source(s):
§ Loose anti-lock brake sensor bolt(s).

Action(s) to take:
§ TIGHTEN the anti-lock brake sensor bolt(s) to specification.


Good luck!

Steve

 

I had the exact same problem (ABS engagement during low speed stops) on my 99. However, even though the front wheel speed sensors looked fine when I replaced them the problem went away. So did the panic stops! Good luck.

 

Thanks for the input guys, I will work on it this weekend and let you know what I come up with.