It should not stop the lockers from engageing as the centre diff lock turns off the abs when it is engaged. DO NOT engage the lockers on pavement. Go to a gravel road or parking lot. Shift into low to engage the centre diff lock. Engage the fr & rr diff locks and drive around a bit. If the front engages the steering will get very stiff and you know everything is working as the front will only engage once the centre and then the rear engage.