Rear Wheel Bearing track life?

[R13]

I still have the dust shields, but I've notched them on one side so I can get them off without having to remove the hub/bearing assembly. I don't think it's a dragging caliper. The only reason is that, of the two rear wheels the driver's side is usually marginally cleaner than the passenger side so if anything I would suspect the opposite caliper vs. the one on the side with the bad bearing.

 

[R13]

Small update:

I've been out of town and so am just now getting around to this.... I'll have the new bearing assembly pressed onto the hub tomorrow. I'm going to ask the shop to measure as closely as possible the symmetry of the hub while the two are separated. I'll also be dropping off my entire set of wheels (the ones that have been on the car during afore-mentioned shenanigans) for inspection and re-balancing.

In the meantime, I've decoupled the shock and axle from the knuckle and the good news is the ball joints show no play at all and none of the control arms appear bent or cracked. The bushings all appear to be intact on that left rear corner.

I'll update with the shop's findings later in the week. Once I have the re-assembled bearing back on the car, I'll proceed to road test the car with the OEM hubcentric 15/16" wheels shod with evenly-worn tires to see if any shimmy or vibration persists.

 

[freespace303]

I know this is a bit of an older post, but I believe my front left wheel bearing is need of replacing, but not really sure. Are there any reputable shops, with actual NSX experience, in the VA area? Thanks!

Here's a post/video I made when discovering the "noise" my wheel bearing is making.

http://www.nsxprime.com/forum/showt...ain-noise-at-speed-What-is-this-sound-(video)

 

[R13]

I'm not sure that's a wheel bearing. My bearing sounded more metallic than that when it got really obvious and was more of a clicking noise. I would try another set of tires and see if that didn't cure both noises.

That said.....If it's bad enough to make noise, you should be able to confirm by jacking the front of the car up (use a jack stand to be safe), leave the wheel on, and grab the top and bottom of the tire, or spokes....whichever gives you the most leverage, and see if you can wiggle the wheel/tire (push/pull on the top/bottom only, it will always wiggle side to side because steering).

If it wiggles AT ALL vertically, then you've either got a bearing, ball joint, or bushing that's gone bad. If it's really easy to wiggle...probably a bearing. Point of housekeeping: if you can wiggle your front wheel vertically.....'probably shouldn't drive the car.

The bearings are actually not that bad of a DIY, but you'd still need to take it somewhere once you have it off the car to have the hub pressed out/in.

- - - Updated - - -

Also, on-topic with this thread. Left Rear bearing #3 has survived 3 track weekends now.

 

[freespace303]

I'm not sure that's a wheel bearing. My bearing sounded more metallic than that when it got really obvious and was more of a clicking noise. I would try another set of tires and see if that didn't cure both noises.

That said.....If it's bad enough to make noise, you should be able to confirm by jacking the front of the car up (use a jack stand to be safe), leave the wheel on, and grab the top and bottom of the tire, or spokes....whichever gives you the most leverage, and see if you can wiggle the wheel/tire (push/pull on the top/bottom only, it will always wiggle side to side because steering).

If it wiggles AT ALL vertically, then you've either got a bearing, ball joint, or bushing that's gone bad. If it's really easy to wiggle...probably a bearing. Point of housekeeping: if you can wiggle your front wheel vertically.....'probably shouldn't drive the car.

The bearings are actually not that bad of a DIY, but you'd still need to take it somewhere once you have it off the car to have the hub pressed out/in.

- - - Updated - - -

Also, on-topic with this thread. Left Rear bearing #3 has survived 3 track weekends now.

Thanks man, I'm actually in the market for some new tires, since I'm getting sick of my loud Khumo Ecsta XS's. Any suggestions? Feel free to reply to the thread I made here...

http://www.nsxprime.com/forum/showthread.php/177818-Best-tires-for-Wear-Noise-Value

Thanks!

 

[R13]

.....and the 4th event was the charm.

cheap-o bearing #3 is in the can. This one was just starting to click/develop some play after a weekend at Barber Motorsports Park followed by an autocross.

I just ordered a pair of them from rock-auto for half of what an OE bearing would cost. Silver lining: I'm down to like 15 minutes for removing the assembly from the car.


I may explore re-packing the extra new bearing I got with some *real* grease. I've heard a main difference between an OE Honda unit and the 3rd parties is the grease.

That failing, I may finally break down and try a Honda OE bearing. If that fails, then I'm going to look at replacing the knuckle because something can't be right at that point.

I'll keep this updated.

 

[3gGT]

.....and the 4th event was the charm.

cheap-o bearing #3 is in the can. This one was just starting to click/develop some play after a weekend at Barber Motorsports Park followed by an autocross.

I just ordered a pair of them from rock-auto for half of what an OE bearing would cost. Silver lining: I'm down to like 15 minutes for removing the assembly from the car.


I may explore re-packing the extra new bearing I got with some *real* grease. I've heard a main difference between an OE Honda unit and the 3rd parties is the grease.

That failing, I may finally break down and try a Honda OE bearing. If that fails, then I'm going to look at replacing the knuckle because something can't be right at that point.

I'll keep this updated.

I know this is a very old thread, but I'm wondering if you ended up going with the OEM wheel bearing assembly or not.

Thanks,
3gGT

 

[R13]

I'm still on the last parts-store / timken bearing. However, in the meantime I've replaced all of the ball joints on the entire car (via Steve Ghent's services) and had it re-aligned. I'm now on 2 track days and three cross-country (TN->CO, CO->CA, CA -> CO, CO->TN) drives since I last replaced the offending bearing. So I don't have enough data yet to call it fixed as the previous best lasted 3 track weekends.

 

[bj91nsx]

Cant go wrong with OEM bud. That's your best bet. I mean is it really worth the extra time and headaches of changing bearings all the time?? Just wondering...

 

[R13]

Cant go wrong with OEM bud. That's your best bet. I mean is it really worth the extra time and headaches of changing bearings all the time?? Just wondering...

Because it doesn't particularly make sense for a single corner to keep wearing out at ~4x the rate of the others when they're all the same non-oem part. It's principle at this point, lol

 

[Midnight_Raven]

So in regards to your first symptom of the wheel shimmying at around 65-70 mph, did changing the bearings with this latest set fix that?

I'm in the same boat. After my about 15 autox and 1 track day I started having a vibration on my wheel at that speed range 65-75mph. I'm thinking it's one of my wheel bearing, but before I started to replace those, I've been eliminating away all the possible problems that could cause this. 1st I had my RE30 and NT01 rebalanced. That didn't seem to remove the vibration issue. I then refinished my Model 5s and installed new ZIIs on them. That still didn't fix issue. I then took the car to the local NSX specialist (Mechanics Direct) and had them inspect all suspension components and they told me everything checked out good. No play in the wheel bearings or other suspension components. They think it could be two things, either one of my coilovers could have a slight internal leak or one of the wheel bearings is starting to fail but only under load. The more aggressive offset could be causing this issue but they just have no way to test this out.

I'm contemplating on just replacing the front bearings but am wondering if that even fixed your issue or not?

 

[nsxnut]

So in regards to your first symptom of the wheel shimmying at around 65-70 mph, did changing the bearings with this latest set fix that?

I'm in the same boat. After my about 15 autox and 1 track day I started having a vibration on my wheel at that speed range 65-75mph. I'm thinking it's one of my wheel bearing, but before I started to replace those, I've been eliminating away all the possible problems that could cause this. 1st I had my RE30 and NT01 rebalanced. That didn't seem to remove the vibration issue. I then refinished my Model 5s and installed new ZIIs on them. That still didn't fix issue. I then took the car to the local NSX specialist (Mechanics Direct) and had them inspect all suspension components and they told me everything checked out good. No play in the wheel bearings or other suspension components. They think it could be two things, either one of my coilovers could have a slight internal leak or one of the wheel bearings is starting to fail but only under load. The more aggressive offset could be causing this issue but they just have no way to test this out.

I'm contemplating on just replacing the front bearings but am wondering if that even fixed your issue or not?

A CV Joint going out can cause a shimmy. After almost 20 years and 150+ track days I replaced my OEM wheel bearings.

 

[R13]

Because it doesn't particularly make sense for a single corner to keep wearing out at ~4x the rate of the others when they're all the same non-oem part. It's principle at this point, lol

Also, I'm down to like 45 minutes for the whole operation (and still haven't had to do a rear again)

So in regards to your first symptom of the wheel shimmying at around 65-70 mph, did changing the bearings with this latest set fix that?

I'm in the same boat. After my about 15 autox and 1 track day I started having a vibration on my wheel at that speed range 65-75mph. I'm thinking it's one of my wheel bearing, but before I started to replace those, I've been eliminating away all the possible problems that could cause this. 1st I had my RE30 and NT01 rebalanced. That didn't seem to remove the vibration issue. I then refinished my Model 5s and installed new ZIIs on them. That still didn't fix issue. I then took the car to the local NSX specialist (Mechanics Direct) and had them inspect all suspension components and they told me everything checked out good. No play in the wheel bearings or other suspension components. They think it could be two things, either one of my coilovers could have a slight internal leak or one of the wheel bearings is starting to fail but only under load. The more aggressive offset could be causing this issue but they just have no way to test this out.

I'm contemplating on just replacing the front bearings but am wondering if that even fixed your issue or not?

Yes, I have eliminated the steering shimmy (reasonably confident with a couple thousand miles and an autocross under the belt since). I replaced both front bearings at the same time I had the ball joints replaced and un-seized the caster adjustments so that could be correctly adjusted/evened from side to side. Somewhere in that space was the solution.

 

[Midnight_Raven]

Thanks for answering that. I guess I should start with the front wheel bearings then. If that doesn't work I might have to do the other items as well.

 

[R13]

So 'xpo '16 at Sebring finished off cheap-o bearing #5 it seems.

Negative: means that this one, although installed before rear ball joint replacement, none the less wore out afterwards.

Positive: Rock Auto had a clearance on bearing assemblies, so I got a couple for SUPER cheap.

On to (SUPER) cheap bearing #6 on the left rear. Right rear, and both fronts still completely intact (also bargain-brand assemblies/bearings) since beginning of this thread.

 

[R13]

The saga continues. (SUPER) cheap bearing #6 survived two days at VIR with no drama whatsoever and not a wiggle off of my match mark. Since then I've done one autocross (again, no movement) and then subsequently killed #6 at Charlotte Motor Speedway (or at least I can see my match mark on the axle nut has backed off a mm or two, which has here-to-fore been indicative of a dead bearing).

This does bring up another point: I can no longer speculate that it's just stress related to that particular corner of the car. All of the other bearings have been killed on tracks that are predominantly right-handed with lots of heavy loading on that outside rear. Charlotte though, even with the infield course, is largely one big rather-high-G left hand turn with a couple of right hand hairpins/kinks in between.

Just to recap:
Right Rear: Off-brand (Timken IIRC) wheel bearing. ~6+ years old, dozens of track events
Left Rear: Now on off-brand bearing #7 (once I swap this one on).

Have replaced:
ALL ball joints
LR Knuckle
Bearing itself 7 times
Wheels
Tires (repeatedly obviously)
Toe link

About the only pre-first-problem parts left are inboard bushings, the KW V3 dampers/springs, the hub, and the CV/axle assembly (which was also rebuilt with Driving Ambition rebuild kit and grease circa 2009/2010).

At this point I'm having two thoughts:
1) Chicken or Egg: is the bearing starting to fail, and leading to the axle nut moving OR is the axle nut moving, and allowing the play that leads to the bearing failing?
2) If we extrapolate from the perspective of the axle nut loosening leading to the bearing failure, would it be reasonable to put the hub under some scrutiny? Could an imperceptible warp in the hub be preventing the axle nut from seating properly with the book-specified torque (+5-10ftlbs this last time) such that it starts backing off under very-heaving braking and then leads to bearing failure?

 

[crxguy52]

I've been giving this some thought, and the failure modes I can come up with for a bearing are:

- Excessive loading
- Excessive heat
- Manufacturing defect
- Excessive\insufficient preload on the inner\outer race, radially
- Excessive\insufficient preload axially

I think we can rule out excessive loading , since the other wheel bearings aren't failing. Heat is also an unlikely cause, since the other rear wheel bearing sees similar temperatures. Multiple bearings would indicate it's not a manufacturing defect.

I would guess it's a preload issue, either radially or axially. Given that the upright and hub haven't changed they might be in question, but I think the most likely culprit is the axle nut backing off and un-preloading the bearing. I saw a thread where others had an issue with the axle nuts backing off, might make sense to check your witness mark between the axle and nut after every session and re-torque if necessary.

 

[R13]

I've been giving this some thought, and the failure modes I can come up with for a bearing are:

- Excessive loading
- Excessive heat
- Manufacturing defect
- Excessive\insufficient preload on the inner\outer race, radially
- Excessive\insufficient preload axially

I think we can rule out excessive loading , since the other wheel bearings aren't failing. Heat is also an unlikely cause, since the other rear wheel bearing sees similar temperatures. Multiple bearings would indicate it's not a manufacturing defect.

I would guess it's a preload issue, either radially or axially. Given that the upright and hub haven't changed they might be in question, but I think the most likely culprit is the axle nut backing off and un-preloading the bearing. I saw a thread where others had an issue with the axle nuts backing off, might make sense to check your witness mark between the axle and nut after every session and re-torque if necessary.

I'd found that thread at some point. To the second factor Ken mentions there though: I've now had a failure at a predominantly left-handed track (grant it, VIR prior to that was predominantly right-handed, and the nut didn't move). Also, Would preload be applicable to the big sealed bearings? I thought that was more of a thing for split bearing setups (or are we talking just the "tightness" load keeping everything snug between driveshaft,axle and bearing)?

Other observation: The match marks have backed off a mm or two, but I did throw my big-ass torque wrench back on it today and it did not re-match the marks even at 250ftlbs (spec is 242). So it common terms it's not "loose". It has, however moved. This weekend I may look closer to see if/how much bearing play exists.

Thinking more, I wonder if the left rear is particularly susceptible to the nut moving under braking force on account of weight distribution and the direction of the forces acting on the assembly under braking? I need to draw that out to visualize, but I think under braking, the rotational forces would be trying to back the nut off on the left side, where on the right side, it would have the opposite effect......I'm just spit-balling at this point.

[edit] nevermind, direction of rotation should have no impact because the driveshaft splines deal with all of that. [/edit]

 

[crxguy52]

I'd found that thread at some point. To the second factor Ken mentions there though: I've now had a failure at a predominantly left-handed track (grant it, VIR prior to that was predominantly right-handed, and the nut didn't move). Also, Would preload be applicable to the big sealed bearings? I thought that was more of a thing for split bearing setups (or are we talking just the "tightness" load keeping everything snug between driveshaft,axle and bearing)?

Other observation: The match marks have backed off a mm or two, but I did throw my big-ass torque wrench back on it today and it did not re-match the marks even at 250ftlbs (spec is 242). So it common terms it's not "loose". It has, however moved. This weekend I may look closer to see if/how much bearing play exists.

Thinking more, I wonder if the left rear is particularly susceptible to the nut moving under braking force on account of weight distribution and the direction of the forces acting on the assembly under braking? I need to draw that out to visualize, but I think under braking, the rotational forces would be trying to back the nut off on the left side, where on the right side, it would have the opposite effect......I'm just spit-balling at this point.

[edit] nevermind, direction of rotation should have no impact because the driveshaft splines deal with all of that. [/edit]

If you look at the top right of page 18-32 in the service manual, the cross section shows that the bearing is composed of two angular contact bearings. These types of bearings need to be preloaded axially in order to support a radial load - this is why the axle nut torque spec is so high. If the nut was just holding the axle in, the torque spec could be a lot lower.

That's curious that the nut didn't move when you torqued it - I'd be curious what happens if you un-staked it, loosened it, and re-torqued it (assuming the bearing is still good). I can't think of a scenario where the bearing would cause the nut to back off, it would take an awful lot of force to do so. Have the match marks on the other side moved at all?

The braking moment is reacted by the suspension, not the axle, so the only torque on the splined joint would be from the engine braking\drive torque. Engine drive torque significantly outweighs engine braking, but even if there was play in the splines you'd think it would tighten the nut. Do the match marks indicate the nut has tightened? Excessively preloading the bearing could kill it pretty quickly.

Not an expert by any means, just trying to think through what would cause this.

 

[R13]

I did jack the rear up and I can't detect any obvious play in the bearing at this point. Historically it has developed a wiggle any time the nut has moved. I may try unstaking it, loosening and then re-torquing to see if the paint marks line back up. I assume the nuts are single start. Which "other side" are you asking about? The right rear? If so, no, it has never moved.

It's definitely backing off, not tightening. You can see the gray match marks as well as where the stake has moved some (pardon my messy staking)

 

[docjohn]

one side tightens the other loosens...I have had this happen pm Larry B he may have some thoughts on tracked cars with R tires.

 

[R13]

one side tightens the other loosens...I have had this happen pm Larry B he may have some thoughts on tracked cars with R tires.

I had that thought, but ruled it out (as above) since I'd think the splines should prevent that type of counter-torque from making any headway unless we're at the level of minute vibrations? Was it quite so chronic in your case and/or did you find a solution? I'd thought about pinging Larry or seeing if I could track down Barney to get the mechanical wizard opinion, I suppose I should probably follow through.

 

[docjohn]

nope just chalked it up to dealer not torquing to spec...

 

[crxguy52]

I had that thought, but ruled it out (as above) since I'd think the splines should prevent that type of counter-torque from making any headway unless we're at the level of minute vibrations? Was it quite so chronic in your case and/or did you find a solution? I'd thought about pinging Larry or seeing if I could track down Barney to get the mechanical wizard opinion, I suppose I should probably follow through.

I would imagine it wouldn't take much motion to back the nut off if it happened cyclically. The spline interface is always going to have some play, otherwise it would never go together.

At a high level it appears the RR and LR bearings are in almost identical circumstances, except on one side the nut is backing off and the bearing is failing. Might be worth un/re-torquing when it starts to back off. LarryB probably has more insight.

 

[latzke]

Pardon the 101-level questions:

All mating surfaces the axel nut touches are 100% dry/clean (no oil, grease, paste, dirt, etc on driveshaft threads or flat surface the washer touches) before nut is threaded and torqued?

Can the staking be done in a manor that provides positive retention, where nut cannot reverse as seen?