I have a ? on the abs light. Im in the process of changing out that Ball Joints . I figured while I was at it I would fix the ABS light that been on for some time. How do I figure out which sensor is bad? I know I dont want to replace them all bc they are between $170(Motorcraft)-$70(Cheap one).

I am just wondering if there is a way I can track this down and figure it out

 

not to be the bearer off bad news, but mine did this and it was my hubs going bad.
i have seen where you can jack up the tire and spine it will having a meter plugged in to the abs sensor/

 

But the good news is,you can get Timken brand hubs from Autozone for about $160...and I believe they come with new ABS sensors..
Edit..not sure if the f550s are the same though..

 

Here are some ohm and voltage tests you can run.

Front ABS Sensor Ohm reading across the Sensor End connection

4x2 F250/350: 2,000-4,000 ohms

4x2 F450/550: 650-800 ohms

4x4 F250/550: 650-800 ohms

Rear ABS Sensor (VSS) Ohm Readings

All: 800-3,500 ohms

A volt meter, set to the low scale AC volts, should show a fluctuating reading while the differential, or front hub, sensor ring is turned at a quick rate.
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