Front wheel ABS sensor sheared and Fallen into Hub! (1 Viewer)

[OkavangoCruiser]

Hi guys,

I originally posted this on the 100 series forum, but since mine is a 105 series, it has more mechanical affinities and duplications from the 80 series...

I realise the ABS wheel speed sensor's have been discussed before but...this one I think is a little unique and I'd like to ask if anyone can point as to the cause, so I can check the components out properly.
Vehicle: 2006 LC 105 Series (solid front axle) 1HZ 4.2 diesel (non-turbo)

The ABS light came on when I was making a difficult u-turn (on soft ground) using low range yesterday...did the usual searching through my manual and the forums and managed to work out how to read the fault code off the flashing ABS light on the dash: "32" - a big thanks to the dudes who posted that info!!

This indicated a front left ABS wheel speed sensor fault. I removed the wheel and then the sensor in question, bolted in from the top of the swivel hub, whereupon I discovered to my surprise that only part of the sensor came out of its housing, basically a short part of the shaft ending in two small aluminium flat-pins with bits of copper wire hanging off the ends (the inner remains of the sensor)! Shining a light into the swivel-hub through the sensor hole I could clearly see strands of thin copper wire (from the innards of the sensor) coating the greasy pulse-ring on the inside of the swivel hub, the remainder of the sensor (smashed?) surely laying somewhere at the bottom of the steering swivel hub or liberally distributed throughout the workings of the cv joint inside!?

Does anyone have any idea how this might have happened? I looks like, from the base of the sensor, the the lower part of it (the shaft which projects down to almost make contact with the pulse-ring and receive the pulses from it) was "sheared off" about 1/2" near the top, closest to the sealing o-ring. Almost as if strong wheel articulation caused the outer axle-hub assembly and it's pulse ring to "flex" and touch the end of the sensor, abruptly tearing it off? But, that shouldn't happen?

I haven't checked play in the wheel (bearings) yet - but by hand with the wheel off it seems tight.

See attached image...arrow indicates where the sensor bolts into the knuckle - there is no hole on the diagram but it fits exactly there.

Any clue?

Thanks!

 

[Locked79]

Possibly the needle bearing/ brass bush in the spindle is that worn it has allowed the cv/tone ring to come in contact with the sensor.

Or the sensor has degraded and fallen apart by itself.

 

[OkavangoCruiser]

Thanks Locked79, makes sense.
The top remainder of the sensor indicates a very fresh "shear point" so it seems to me it was "touched" and broke off quickly, and only a few days ago. Thanks...will check that out. Best regards from this side of the ocean.

 

[OkavangoCruiser]

My Cruiser ABS light came on. After some sleuthing it was the sensor front left. Took it out but most of it was still in the knuckle and mangled in the cv. Brass bush at the rear of the stub axle was loose and worn on the ID. Bought the upgrade kit which includes a needle bearing set from Toyota. The previous eedjuts who worked on this vehicle didn’t even put the lower steering arm cone washers back in, and just filled the cv-knuckle joint with normal wheel bearing grease. . Redid the whole lot this afternoon, torqued to spec, reset the ABS and test drove. Seems a-ok Saved myself by reading the manual and watching YouTube. And consulting IH8MUD! Ja well the previous feckwits that worked on the Cruiser didn’t help by using wrong lubricants which I’m sure led partially to this...they replaced both CV’s 3 years ago. Anyway the needle bearings pressed in nicely (so fragile) after freezing them for an hour and the old bush I merely trimmed down to size of the new one, so now I have a new one for the RHS (no doubt it’ll also be filled with the wrong grease). Tested again and feels and sounds good. Will post a few images...

 

[OkavangoCruiser]

 

[OkavangoCruiser]

One can see all the copper wire from the innards of the (very expensive to replace $120) sensor! And the “loose” full length brass bush. Since the OD of this brass bush is the same as the thinner new one (less than half the length, to accommodate the needle bearings deeper down the throat of the stub axle) I trimmed it down to same length and just put it back. It still doesn’t fit into the top edge of the stub axle tightly, actually it’s loose, so I measured the upper throat of the stub axle and as I guessed it’s oval. So, I will have to replace the stub axle when I’m feeling flush with cash again! But for now she’s pretty tight due to the needle bearings holding the shaft quite sweetly. Will use the new bush on the other side, and insert needle bearings as well. Hoping it’s fine. Cheers all.

 

[shocktower]

One can see all the copper wire from the innards of the (very expensive to replace $120) sensor! And the “loose” full length brass bush. Since the OD of this brass bush is the same as the thinner new one (less than half the length, to accommodate the needle bearings deeper down the throat of the stub axle) I trimmed it down to same length and just put it back. It still doesn’t fit into the top edge of the stub axle tightly, actually it’s loose, so I measured the upper throat of the stub axle and as I guessed it’s oval. So, I will have to replace the stub axle when I’m feeling flush with cash again! But for now she’s pretty tight due to the needle bearings holding the shaft quite sweetly. Will use the new bush on the other side, and insert needle bearings as well. Hoping it’s fine. Cheers all.

I am pretty sure you can only use either the bushing, or needle bearing, to bad ya live so far away, I have some ABS sensors

 

[OkavangoCruiser]

Thanks...I'll keep checking this left hand one at intervals to make sure the needle bearings are holding despite the oval nature of the throat further outwards (where the bush is). The bush seems to be a nice insurance policy in case the needle bearings go...then again, you probably wouldn't notice it until it's too late! Cheers. If I need a sensor again, I'll give you a call...I have clients that come on safari from the US fairly regularly -- thanks!