Strange ABS-problem

[Danish Farmer]

Hi Truck Stop

Recently had my Silverado at the mechanic because the ABS light was on. He changed a bad sensor at the right front to fix it.
But now the ABS is strange. When stopping, the last 5 feets, the ABS kicks in at the left front wheel. Buzzing, making the pedal hard to press and forces the truck a bit to the right. But the light is not on.

He says it can be caused by a fault read out on a rotor, but could not see anything wrong wiht them. And they are both new with aprox 1000 miles on them.

How do I solve the problem ?

best regards
Danish Farmer

 

[THEFERMANATOR]

Has this truck been used where they salt the roads? If so it is fairly common for rust to build up and cause the wheel speed sensors to push out which increases the gap from teh sensor to the tone rung. A small change in the gap isn't noticeable at high speeds, but at low speeds it will cause teh speed signal to become irratic and drop out which will engage the ABS. I would start off by removing the left front hub bearing(I'm assuming this is a 4X4), and remove the wheel speed sensor, clean the tip off, clean the base against the hub where the sensor seats, and reinstall it. Many times it will be only a small change in the gap that will cause this to happen.