ABS kicking in

LB7_01DURAMAX

New member
Apr 11, 2019
20
1
3
Ohio
So I’ve been dealing with this issue for a while. I pulled my ABS fuse because below 10mph the ABS will kick in and pulse and brakes get bad. With the fuse out obviously I don’t have ABS but the brakes feel good. With the fuse in and under 10mph it does not pulse. Has anyone had this issue? Electrical? ABS module internals? I did have my scanner on it and the front left wheel sensor was flaking out so I replaced that and it still does it. Any insight would be appreciated.
 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,874
31
48
41
ZEPHYRHILLS, FL
99-02 trucks had alot of problems with the abs ground causing issues. It is at the cab mount, drivers side, just behind the front tire. That said, low speed activation issues are almost always either rust built up on the hub bearing that pushes the sensor out making to big of an air gap for the sensor to give a good reading at slow speeds(the sensors are all magnetic pulse and are very sensitive to air gap). Or failing hub bearings cause the air gap on the sensor to open up or hit the sensor tip as you load the wheel bearing.
 

LB7_01DURAMAX

New member
Apr 11, 2019
20
1
3
Ohio
Yea when I changed the sensor I cleaned up where it met, it did have some rust build up there. I also took that ground by the cab mount cleaned it up and put it back on. Didn’t help
 

Ron Nielson

Member
Oct 11, 2009
341
21
18
Berryton, KS
What codes are present on your truck? Any modules that you cannot communicate with, based on a scan tool plugged into the DLC (diagnostic link connector)?
 

clrussell

pro-procrastinator
Sep 23, 2013
5,671
194
63
Put your scan tool back on and watch data. One of the sensors is dropping out at slow speeds.

replace that wheel bearing assembly and sensor. Not just the sensor