O-Ring inside the dust seal between the knuckle and CV axle disintegrated...

Hi all,
I replaced the driver CV axle today, (had a torn outer boot). Now when I got in there I believe this part 90301-A0005, https://toyotaparts.mcgeorgetoyota.com/oem-parts/toyota-bearing-o-ring-90301a0005 (an O ring) had more or less disintegrated. Now I was doing this in my gf’s driveway and didn’t have another vehicle to go to a part store and get this part. Nor am I 100% sure this is indeed the O Ring that disintegrated. Basically, there was some thin rubber in a semi circle inside the CV/Bearing dust seal- https://www.autozone.com/drivetrain...PLA:US:EN:AD:NL:1000000:HRD:71700000043798718

So I installed the CV and bolted it all back up... my question is, do I need to get this O-Ring, crack everything back open, and install? Does anybody know the prime function of that ring? Is it possible this is not the ring that dissolved and was just some torn rubber?

Hopefully this makes sense.

 

Did you unbolt the hub from the spindle?
The O-ring is between the hub and spindle.
You don’t have to remove the Hub to get the axle out.

There are 2 dust seals for the axle.
One in the back of the spindle and one on the axle.

The rubber dust you seen was probably worn dust seals.
It’s best to replace them, especially when doing hubs.

Honestly, if you are rolling on stock bearings at high mileage, I would just wait.
The Avg. seems to be 100k-150k on the front bearing.

It’s up to you. If you already have it back to gather, well.....

 

Thanks for your reply. No, I didn’t remove the bearing. I just unbolted the knuckle from the LCA. This is good to know- the bearing is pretty new (20k ago or so). I think you’re right- it was probably from some rubber from the dust seal. The dust seal is also new as of 20k ago, and seemed to be in good shape. Given this I think the install was smooth and I am not missing an O-Ring. Thanks!