Tracking down vibration and noise

[Looger]

19 Accord LX 1.5T, CVT transmission.
100k miles. Busted up Michigan roads

Slowly developed vibration and noise that isn't noticeable until above 30mph.
Becomes louder with with speed. Not super loud--but a very noticeable rhythmic droning.
Character does not change with acceleration, stopping, turning, etc. Just volume and of course, tempo.
Can feel it through the gas pedal/floor area, and a bit through the steering wheel.

Tires seem ok, low mileage CC2, RE-balanced several times to rule them out.
DT said rims look fine.

No play in wheel bearings.
Checked with stethoscope, dead silent except the shhhh sound likely from the pads.

All other suspension components appear in good shape, and are tight.
However, my specialty was drivability (with solenoid carbs, about a million miles of vacuum line, lean burn ignition, etc), so I admit heavy was never my bag.

The intermediate shaft bearing had clicking detectable with stethoscope, and I had a substantial amount of movement at the inner CV joint and/or the intermediate shaft bearing. Hard to tell which allowed the movement.

Driver's inner CV had just barely detectable movement, with a faint click.

Replaced the passenger axle and intermediate shaft with OEM parts, which improved the issue substantially.
However, there is still a noise/vibration...

I believe I fixed one of two issues.
There is a lot less midrange tone, but what remains is a lower frequency tone.
My best guess is the driver's CV axle is on the way out.

Silly question: is it possible for a wheel bearing to be bad, but not noisy?
The stethoscope has impressive amplification, so I doubt it. I definitely had the probe right on the bearing housings.

Though I doubt they are the issue, I'm also considering a 2nd opinion, just to be sure to rule out tires or rims.
Sometimes a different set of eyes can pick things up.
Forgot to mention that the wheels have been rotated several times, with no notable change in the noise/vibration.

Thoughts from the awesome BITOGers?

Bob

 

[walterjay]

Could the car frame have been slightly bent by running over something? One of my cars years ago got run up on a curb with a small dent below the rocker panel. Vibration forever after that.

 

[Looger]

Oh, interesting thought.
I'll keep that in mind, thanks.

Bob

 

[JDenyer232]

How did you use the stethoscope, were the wheels in the air? Bearings under load from the weight of the car can make noise, remove the load and they can go silent. Wheel bearings can be tricky to diagnose at times. The best tool is a remote microphone so that you can hear what they sound like under load. Steel man tools just google it, sells a set for $100, it could end up saving you money and aggravation from not having to replace good parts. Also check the transmission housing for noise, where the axle shafts enter the transmission. I doubt its the transmission but it doesn't hurt to check. Also check the usual suspension components like ball joints and tie rod ends for any slop. You can use a the remote microphone to check for abnormal noise on any component. No I don't have any interest in steel man tools. It just happened to be one of the first ones to pop up with a cheaper one that's adequate for a home mechanic. Edit: Spelling

 

[Looger]

I did not fully consider loaded vs unloaded, thanks! I assumed that it would at least have some noise unloaded...

I did consider the Steelman system as well, even if just to isolate the noise to a corner.
Even have it on my Amazon wishlist.
I was a little concerned by some of the reviews that indicated large differences in volume from channel to channel.

It drives me a little nuts purchasing an item that will likely only be used once...but, the investment could be a time and money saver overall.

I searched for vibration sensors, but wasn't able to find much that was reasonably priced that would work in this application.

Total side-note.
I bought the HyperTough cordless impact wrench (alleged 900ft/lbs) , because my old impact was only rated to 350ft/lbs. Wanted to assure removal of the axle nut.
The reviews are real: the thing is a beast. It takes a couple seconds to rev up, but then really cranks.

Bob

 

[JimPghPA]

Probably not the problem, but keep in mind that the front struts have bearings on top to allow the spring cap to turn. They can wear out. There have been post about replacement quick-struts not having the same angle as originals. So, if you replace them, keep the old ones. Sometimes, one has to put the new ballbearings in the old top pieces to get a final usable replacement / rebuild.

And of course, if you do that, have it properly in a spring compressor before removing the shock top nut.

 

[dbias]

I did not fully consider loaded vs unloaded, thanks! I assumed that it would at least have some noise unloaded...

I did consider the Steelman system as well, even if just to isolate the noise to a corner.
Even have it on my Amazon wishlist.
I was a little concerned by some of the reviews that indicated large differences in volume from channel to channel.

It drives me a little nuts purchasing an item that will likely only be used once...but, the investment could be a time and money saver overall.

I searched for vibration sensors, but wasn't able to find much that was reasonably priced that would work in this application.

Total side-note.
I bought the HyperTough cordless impact wrench (alleged 900ft/lbs) , because my old impact was only rated to 350ft/lbs. Wanted to assure removal of the axle nut.
The reviews are real: the thing is a beast. It takes a couple seconds to rev up, but then really cranks.

Bob

I’m 61 and have replaced at least a dozen wheel bearings in my time.
I’ve had them be noisy, no stethoscope just a long screwdriver placed on the knuckle and pressed against my head behind my ear, and most all had a clicking noise instead of the smooth swooshing sound of a good one.
Almost none of them have had the slightest amount of slack in them when doing the obligatory push and pull on the tire at 12 & 6.
I am sensitive to any sort of noise made by my cars and I guess I just catch them super early. However I did have one jump up and catch me off guard on my 2003 GMC Denali Sierra. I had just driven it the day before my son took it five miles from home to the park and when he got there he called and said he heard a cracking sound while driving. I told him to come straight home after he was done at the park and when he came home I could hear the noise and as he turned to pull into the driveway I saw three or four bright orange ball bearings bouncing off the road. It was toast. Smoking and got so hot that it melted the boot on the CV joint on driver front.
If any of your wheel bearings sound the least bit different especially if they are the ones where you had the CV issues I’d keep an eye on them as that’s likely where you are getting the noise/vibration from. One thing for sure is if it is a wheel bearing it will only get worse and let you know for sure and eliminate the parts cannon.

 

[Looger]

Great replies, thanks.

I have heard that the strut bearings can cause some odd stuff...

Yes, I'm also super tuned into odd sounds and vibration.
Not many believe this, but different oils change a vibration in my car to the point that there is a rattle that occurs in my dash.
I think it is just a fluke of frequency making the component move.

 

[Looger]

Follow up:

I checked all the tires and rims for radial and axial run-out. All good.
I also picked up a screw, and when Discount Tire did the repair, they also re-balanced and rotated the wheels. Said they were off only a little.
This did help a bit with the vibration and noise, but I think there was a stacking effect with 2 or more issues at the same time.

Quick side note: I know balancing is very dependent upon the tech, but it seems like the CC2 requires frequent rebalance. Not even sure if that is possible for a well-maintained tire...but seems like it.
Also, the noise and vibration really makes me think wheel/tire..but DT can't find any issue (not could I).

Anyway, I used the basic Steelman mic system. It was challenging to find a solid place to clamp the mics, as I really wanted to rule out wheel bearings.
I also kinda goofed because I wanted to place a mic near the transmission output, but forgot.

The results weren't as well-defined as I had hoped, because the mics are very sensitive, but I still think I found the issue(s).

Driver rear was very quiet.

Driver front: there was a little noise here, with faint droning that, of course, correlated with the baseline problem.
I'm guessing the CV axle is making a little noise.

Passenger front: while stopped, the mic had some annoying low-volume baseline white noise.
But it became super loud as the speed increased, and I could hear droning underlying the white noise.
I could hear a very faint drumroll sound as well.
And, when loading the wheel, there was a prominent and loud metallic clattering.

I think this is the offender.
However, there are are a couple of confounding issues.

After replacing the passenger CV axle and intermediate shaft with genuine Honda parts, there is an audible click or pop when turning right into my driveway, as that wheel hits the curb and compresses the suspension. This is heard without the Steelman.
It isn't super loud, but definitely there.
I rechecked all of my work and it is solid.

Rechecked all suspension steering parts on that side and found no issue.
Really paid attention to the ball joint (testing with the control arm supported) and it seems fine, though it was hard to keep the prybar engaged with the ball joint without jeopardizing the rubber or slipping off.

Possible culprits are:
Lower ball joint (doesn't seem so)
Control arm bushings
Lower arm bushing stopper (on control arm).
Sway bar link
Strut bearing/etc.
Compliance bracket (attached to control arm)

Finally the other oddity. The passenger rear. It had some minor baseline noise like reindeer bells, and developed a loud chirping sound like a loud cricket as speed increased.
This noise matched the tempo of the offending noise/vibration.
This means it could be the offender, one of the offenderS, or that it is incidental.
The matching tempo, while critical in diagnosis, does not alone make the case.
In other words, the a component can't be the offender without a matching tempo.
BUT, a component may have a faint matching tempo, but not be the problem, because all of the rotating components are spinning at the same rate.

Darn it.

I'll do my best to inspect the strut mount/bearing.
Then, I'll replace the passenger front wheel bearing and ball joint (can pull the strut to get a good look as well).
Why ball joint?
A couple.months ago I his a pothole that destroyed the tire. Rim looks fine per DT (they checked it twice with the tire off), so maybe the pothole put a flat spot on the ball, resulting in the click...?
And it is inexpensive.

While in there I may replace the control arm bushings. Not sure about the "compliance arm."

To make the repair easier (not have to cut off the bearing race) I could replace the hub for $85.
It is possible that the hub itself is bent...but I doubt it because it would be seen when checking rim run-out.

May also replace the passenger rear bearing/hub assembly as well. It is inexpensive, and doesn't appear to be a difficult repair.

Sigh....more work...

Bob

 

[D1dad]

Old post but worthy of responding. Every bearing I’ve had to replace over the last 15 yrs (all nissan) had no play at all, but made the typical bearing noise. The only fool proof way I’ve found was pulling left and right gradually while going 55mph. Whatever side is bad will quiet down when loaded with more force. I’ve had to beat bearings off with a sledge here in the rust belt, but typically a replacement is a diy and an hour or less. Use some anti seize so the next time isn’t as brutal. I’m at the point that I’ll keep an eye out for deals and stock them to a point that they get replaced as a maintenance item when doing my brakes.