Needing a little help with front hub...I suspect?

[mtm]

Hey guys I'm usually over on ranger power sports but I need a little guidance on my fiances '99 explorer 4.0 4x4. For a while now whenever she hits a dip or bump in the road, the front driver's side sounds hollow. I thought it was because the shocks were junk so while changing the shocks, I realized the rotors needed changed as well. So I changed the rotors, brake pads, and put on new shocks. Before I let it off the jackstands, I noticed that from top to bottom that wheel has a tiny bit of play in it. After replacing the brakes/shocks the hollow thumping sound is still there. Also about a week after I changed the brakes the ABS light came on and has been on since. I've been searching around for the procedure to diagnose the blink on the ABS light but I've come up empty handed. Anyway, I'm thinking this could all be related to needing a new hub assembly. I thought ball joints but the ABS light is pointing me towards the wheel sensor in the hub. I'd really like to be able to pull the code and know for sure. Any ideas?

Thanks
-Matt

 

[my pos mounty]

Sounds to me you are on the right track. The ABS sensor and the wheel play point squarely at the hub/bearing. It sounds like the bearing is worn beyond spec and allowing movement within, this would cause the ABS sensor to come in contact with the sungear inside the bearing assembly, essentially wiping the face off the sensor....result is ABS light. The new hub/bearing would come with a new ABS sensor.
You could double check the ABS sensor by removing it from the hub for a visual inspection, its just 1 allen head bolt. Clean off the face of it and see if it looks like it has been compromised.
I would recommend a Timken hub, pricey but worth it.

 

[mtm]

Thanks for the quick reply. The ABS light didn't kick on until after I changed out the rotors. We also had to use the 4x4 for snow a couple of days before the light kicked on. The dull hollow thumping sound has bee going on for a couple of months now. Since I changed the shocks I can only suspect ball joints or the hub assembly. I'll try removing the speed sensor and see how it looks for the light's sake. Regardless something will have to be replaced to get rid of the thump.

 

[my pos mounty]

Thanks for the quick reply. The ABS light didn't kick on until after I changed out the rotors. We also had to use the 4x4 for snow a couple of days before the light kicked on. The dull hollow thumping sound has been going on for a couple of months now.

If the ABS sensor looks good and you want to get the codes, autoparts stores such as autozone would love to read them for you, then sell you the replacement part. The next logical place to look would be balljoints. I had an unexplained thump and discovered it was my lower balljoint.
Good Luck

 

[Carguy3J]

Be VERY careful trying to remove the ABS sensor from the hub. They are very fragile, and they have a nasty habit of seizing in the hole. Them, when you try to remove it, it just snaps off flush with the hub surface. I have never successfully removed an "old" sensor without breaking it. Since you are pretty sure you need the hiub/bearings anyway, and it comes with a new sensor, just replace the whole thing, and go from there. Even if you find out the sensor is bad, so what? What is that going to accomplish? You still need to replace the hub, as sensors are very hard to find seperately, and cost almost as much (and sometimes more) then a complete hub assembly.

If you want to test the electrical functions of the sensor (resistance), then you can do that by disconnecting the plug (just follow the wire from the sensor up towards the body).

 

[mtm]

Well I went ahead and bought a new hub assembly which came with a new sensor. After tearing it down, I'm glad I did. I'm ashamed to say the bearing was about to lock up. Dry as a bone and choppy. I also removed the speed sensor and it was all chewed up and demolished. So I changed out the hub and torqued everything down accordingly. Now all of the slop that was in the wheel is gone. I haven't driven it yet because I'm putting on rear shocks (PITA BTW) but once I drive it I'll let you guys know if it fixed it. Regardless, that hub assembly was on it's death bed. Unfortunately the auto parts store only had one. I'm going to try to find another one and go ahead and change out the other side just so I know both are good and new. Thanks for the help guys.