It seems the earlier x300s rear abs sensor is encased in a stainless sleeve (and attached to the leads). This seizes into the aluminium hub housing over time. This seems to be a common problem. Later models had a fully plastic piece with a connector socket on it. Will one of these fit into the hub correctly, or is the hub unit also different?

I need to replace the rear right sensor (open circuit) but although I can (after lots of wiggling) turn the sensor in the hub quite freely, it won't lift out at all - maybe just enough of a crack to get penetrating oil in there. I think the plastic module is turning in the stainless sleeve.

What will happen if I attach a slide hammer to the head of the sensor to tap it out? Will it a) come out fully, b) come out but leave the sleeve or c) break off necessitating hub dismantling?
In case b) could I then slide the innards of the replacement into the remaining sleeve, or get the old sleeve out of the hub without dismantling?

Thanks
Tom

 

I ran into this issue when I attempted to clean my rear driver side abs sensor a few months ago. Whatever you do, do not tap the sensor. I made the mistake of doing that and I snapped it off.

It's possible to reach in with some needle nose pliers from the back of the hub (where the axle goes into the hub) and pull it out what's remaining of the sensor that way. It will take some time and squeezing of the metal sleeve, but that's how I did it.
Next time the sensor doesn't come out freely from just pulling on it, I'm gonna attempt to push it out from inside the hub...

 

I know the later rear abs sensors ('97) will not work with the earlier cars. And the earlier sensors are specific to the left and right sides. The right side sensor on my car had been broken and RTVed back together, it was probably done by an unscrupulous mechanic. I replaced it with a sensor from a 97, and it did not work. I put in a used sensor from ebay, and now my abs off light doesn't come on anymore.

 

As above, the model years aren't interchangeable. One is longer than another and so, the distance from the sensor to the reluctor (toothed) ring inside the hub is compromised.


With regard to removal, I had the same issue and found that I could prise the sensor out, by accessing it from the inside part of the hub using a suitable lever. The lever can sit on the reluctor ring and get beneath the sensor, for leverage. It makes more sense when you actually take a look see.

 

Thanks for the advice - I've looked round the back and can just about see where under leverage can be applied over the uj. I've fashioned a slide hammer mole grips hybrid tool with sharp teeth to attempt pulling the sensor out - no point buying a new one of i can't fit it!
If it works i could lend it out!
I'll let you know. ..

 

sogoods point about levering from underneath got it started.
The black aluminium top cap is not very strongly attached to the stainless body, so my twisting the top to pull it out had just broken the internal wiring. A screwdriver can be pushed in between the toothed ring and the bottom of the sensor if the wheel can be rotated to the right position. This can get the steel part moving and you're on your way!
Thanks for the help -another job done.
tom