ABS question

[dave110]

Hi all! I have an issue thats been bothering me. Every now and then my ABS will activate. At first I thought I hit loose stones or an oil patch but that's not the case. Does it pulling a trailer or not and I switched to a new brake controller that's supposed to be ABS friendly. Sometimes I can make it happen by pushing very lightly on the pedal. If I push hard on the pedal it will go away. It only seems to do it at the very begining of the pedal travel when I push down lightly. I'm thinking the sensor in the rear axle but during my search it seems the speedometer usually goes wacko if that goes bad. My speedometer is fine. Anyone have any ideas? :shrug:Thanks

[Mopar1973Man]

Front sensors. If you replace then do it in pairs! Front sensors could be off from your rear being there is a speed difference the ABS is active trying to balance speed from front to rear which actually no off at all but the computer see a difference because of weak/bad sensors.Trailer controller has nothing to do with it. The only thing the trailer controller wants is the brake light signal so it knows you place your foot on the brakes and starts using G forces to calculate brake power to the trailer.

[dave110]

Thank you Sir. Are the sensors themselves available through a parts house?

[dave110]

Ouch! Those things are half the price of a unit bearing assy. Are there any diagnostics I can perform to be sure, like unplugging them to see if the problem goes away? I forgot to mention sometimes when it happens my brake (not abs) light comes on.

[Rogan]

I had a rear axle seal leaking goop onto the shoes, which would make one wheel really grabby, causing my ABS to activate at random times.. Just something to peak at..

[Mopar1973Man]

Ouch! Those things are half the price of a unit bearing assy. Are there any diagnostics I can perform to be sure, like unplugging them to see if the problem goes away? I forgot to mention sometimes when it happens my brake (not abs) light comes on.

No you can't unplug it because then that axle has 0 MPH speed and ABS is lit. The only way to test it with a DRBIII tool from the dealer or a very expensive Snap On tool that might be able to see wheel speed. Even then you might find the wrong speed sensor and replace it and then find out the new one is still offset from the other good one still tripping the ABS light. Hence why I suggest replacing both at the same time. As for prices RockAuto.com has then in stock but still $89 and $112 for left and right...

[dave110]

Just wanted to give an update.This problem justwent away and ever came back...........yet. Gotta love a truck that fixes itself.