Rear differential housing ABS sensor replacement

[Salty Dalt]

I am looking to replace a bad ABS sensor in my rear differential housing, I did a resistance test on the sensor and it proved to be open. The problem is the bolt head is completely rounded. I tried to cut a groove into the middle of it for a flat head screwdriver, but it ended up breaking half of the bolt head. I can't get it out with locking pliers either.
Any suggestions? Thank you.

 

[njbronco]

weld a nut to it. the heat from the weld will break it free and the nut gives you the means to remove it.

 

[Salty Dalt]

weld a nut to it. the heat from the weld will break it free and the nut gives you the means to remove it.

Will the heat melt the plastic sensor?

 

[njbronco]

I thought you are replacing it

 

[Salty Dalt]

I thought you are replacing it

I am replacing it. I don't want the old sensor to melt and get stuck in the differential housing. I'll have to make sure it doesn't start melting while welding. Thanks for the help!

 

[njbronco]

I believe there’s a metal bushing in the plastic. Check out your new one. Other option is to clip/grind/break off the old plastic sensor and then weld. But heat is your answer to getting it off. I don’t think the melted sensor is going to really hurt anything excepl maybe give you a sticky cleanup

 

[koda2000]

If necessary saw off the tab on the old sensor where the bolt went. wiggle/twist/pry the old sensor out on it's hole, They can take some effort to pull out. WD40 might help to free the O-Ring seal. With the old sensor out of the way you can try heat to free the old bolt. but the angle is not very good to work from with the diff in the truck. Worst case scenario you'll need to drill out the old bolt but you may end up having to re-tap the hole afterwards if you dill off-center, but the retaining bolt, while necessary, is not a critical part. It just needs to keep the sensor from coming out and oil from spitting out. You could probably leave the broken bolt in place use a radiator hose clamp around the axle tube to retain the sensor as a work-around.

 

[mostly_broncos]

if you take the rear cover off maybe you can smack it from underneath? put a corner on a steel rod and make a hooked punch if you dont have a straight shot , then you could probably put the new sensor in and clock it then drill a new bolt hole , cast iron is pretty easy drilling and threading

 

[koda2000]

if you take the rear cover off maybe you can smack it from underneath? put a corner on a steel rod and make a hooked punch if you dont have a straight shot , then you could probably put the new sensor in and clock it then drill a new bolt hole , cast iron is pretty easy drilling and threading

Oh that's right, the VSS sensor is on top top of the center section. I was thinking about the vent, which is on the axle tube.

 

[mostly_broncos]

I have a lot of punches so many that I often modify them for a specific job if I have to do it more than once . If you have a torch you could heat a round drift of the right diameter and make it turn a corner then flatten the elbow so its like a prybar . If you can get the round end on the sensor then put the corner on the diff carrier you could pry by smacking the end or the side of it with a hammer as long as you don't hit the ring gear you won't hurt anything.

 

[Salty Dalt]

I have looked into the welding a nut onto the bolt head option and it seems that might be the easiest option, without having to open up the differential. I am going to buy a small welder at Harbor Freight for small tasks like that, I have also needed one for a while. I will keep you all updated on how the bolt removal goes. After that, the sensor should just twist out. I might even change the differential fluid again after driving it around a while to make sure that any contaminants that fell into the housing are flushed out. Thank you all for your suggestions, I am keeping the other options in mind as a back up. If anybody has some experience with repairing the 5R55E transmission, I am having issues which I described on a thread I created looking for some help and advice. Thank you.