MorRyde IS Wheel Bearing Job - Unknown Knock/Thump When Loosening Wheel Bearing Nut

[B380]

Hi all,

Doing a wheel bearing job on my MorRyde IS and on my last wheel bearing. Got the bearing repacked and everything seemed good to go, but when I go to loosen the nut after torqueing it down (to then go hand tight), I got a very obvious knock/thump sound that seems like it's coming from within the hub assembly. You can very clearly hear it in my video here:

https://photos.app.goo.gl/wb1FeGYMycqkPkvMA

Note that I can look at the flat edge of the end of the spindle both before and after this noise and it's not moving, which tells me the spindle presumably isn't moving.

Does anybody have any insight on this? I've already reached out to MorRyde, but they're now closed, so hoping for some info here.


Also, in the video I mention 25ftlb, but it's actually supposed to be 50ftlb, which I've tried but the same thing still happens.

[howson]

B380
Hopefully Jimmer, Cate&Rob or another forum member with more experience than I will chime in. I've done the bearings on my 315RLTS (that has the IS) and experienced nothing like what I witnessed in the video. I'm going to guess that somehow the rear bearing (or front bearing) isn't seated thus the hub can move ('rattle'). But that's a guess only.

I'll be following this thread to see what the resolution is.

Howard

[Jimmer]

I have not yet serviced the wheel bearings on my Independent Suspension, but I've serviced and replaced wheel bearings/races a bunch of times on trailers and cars.

* Did you just replace the inner seal and grease the bearings, or did you replace the bearings and/or races?

The noise is either coming from a release a pressure on the bearings by backing off the nut, or because there is some type of friction/scoring between the nut and the washer that nut rides against. Take off the nut and look at the surfaces of the back side of the nut that contacts the washer. If there is no visible scoring or scratch, you can probably rule out the noise coming from the nut/washer, especially since you don't hear the noise when tightening the nut.

That means the noise has to be coming from a release of pressure on the bearings by backing off of the nut. If you put in new bearings, it's possible that one of the new bearings is defective. To me, it seems like 50 pound feet is way too much to set or preload the bearing. You will be fine with 10-15 pound feet. If you've already torqued to 50, it's possible that you damaged the cage of the bearing and that's what's causing the noise, although I've never seen or heard of this happening. To be on the safe side, I'd get new bearings (and a new seal if you can't get the current one out without bending it) and re-do the job and torque the nut to no more that 15 pound feet. If the noise does not re-occur, then it's pretty much confirmed that one of the bearings is damaged.

Remember, the race and the bearings are a matched pair (once used). If you're going to replace the bearing, you should also replace the race. However, for testing to see if the noise occurs, you can use the existing race. Just remember which bearing belongs where.

[Jimmer]

Here is what Chat GTP says about this issue (note: I think it's wrong for Chat GTP to say that the inner race deforms, it is the cage that deforms):

Question: can i damage the cage of conical bearing by overtightening

Answer from Chat GTP: Yes, you can damage the cage of a conical bearing by overtightening the bearing nut. The cage is responsible for holding the rolling elements (balls or rollers) of the bearing in place. If the nut is overtightened, it can cause the inner race to deform and squeeze the cage, potentially damaging it.

In some cases, the damage may not be visible, but it can still affect the performance of the bearing by creating increased friction, vibration, or noise. In extreme cases, the damaged cage can cause the rolling elements to become dislodged, leading to complete bearing failure.

It's important to tighten the bearing nut to the correct torque specifications, as specified by the manufacturer. This will ensure that the bearings are tight enough to prevent movement and wobbling, but not so tight that they damage the cage or other components. If you're unsure of the correct torque specifications, it's best to consult the manufacturer or a qualified mechanic for assistance.

[Cate&Rob]

I would guess that this noise has something to do with flex of the cage that holds the bearings. It is loud enough that I would suspect the outer bearing. You do not mention new bearings or races, so I expect this is the same parts going back together. I do not think that torquing the nut can deform the bearing cage . . . it is only there to position the bearings until things are assembled. Your LCI or Dexter service info likely says to torque to 50 ft lbs. This is what I have always used and I rotate the hub slowly as I toque the nut. The purpose of this tightening is to make sure the races are seated and that excess grease is squeezed out. I note in your video that you went to 25 ft lbs. The first thing that I would try is going to the manufacturer recommended 50 ft lbs. if the noise is still there, remove the outer bearing and inspect its cage very carefully. Next step would be replacing bearings and races.

Lets us know what you learn . . . this is definitely a curious noise (that I have never heard before)

Rob

[Scott'n'Wendy]

I'd be pulling that hub off and checking out the races and bearings again. Could it be hydraulically locked? Maybe causing movement once loosened?
Or...spin that hub a bunch while tightening to 50ft lbs. Still do it?
Or....after the clunk, keep doing the rest of the procedure...when done..does the hub exhibit any looseness?

[Jlawles2]

Put your and on the rotor when backing off the nut. Feel for movement when the noise happens.

Also put a bottle jack under the torsion arm. I wonder if you are moving the arm just enough that it's making that noise as you slightly move the torsion arm toward the unloaded position. As you tighten the nut it's actually loading the rubber springs. then when you back off the nut, the rubber springs get unloaded.

[B380]

Update: I remembered I bought new bearings last April "just in case", and boy am I happy I did. I went ahead and greased them up, but before I installed them I pulled out my bearing race driver and gave the races a couple of good knocks just in case. They seemed fine, but I was down to my final seal and I wanted to rule out everything I could given that I had no further attempts. Whether it was the bearings or the races being out of place, I don't know, but one of the two fixed it. Still have no idea what it could have been. Someone mentioned hydraulic locking? Maybe that was it.

Also, regarding torque, I was originally doing 25ftlb (before backing off) per a Timken video I saw on YT, but then I found the actual procedure previously provided to me by an engineer at MorRyde, which was 50ftlbs before backing it off. Note that I tried 25 5-10 times before moving to 50 and got the same result every time until I replaced the bearings and ensured proper seating of the races.

[Scott'n'Wendy]

Glad you got it sorted. You'll never know for sure what the issue was. If I was going to take a WAG at the three different things..I'd pick bearing because it has more parts.

[Jimmer]

Yes, glad you got solved the issue. Something was not right, and replacing the bearings solved the issue. It's super that you didn't ignore that minor clicking. Who knows what would have happened if you drove on it. Lesson to all is if something seems a little off, address the issue before it becomes serious. (Other lesson is to carry spare bearings/seals/races)

Did you replace the races when you put in the new bearings? They should be replaced as a set.