Vibration (like buffeting) 68-73MPH new tires, 3 different shops checked

[smokey_2020]

Hope the wisdom of the crowd will help me troubleshoot further. I am stumped. This truck was one of the smoothest riding highway cruisers, zero vibrations for 49,000 miles of any kind up until recent episode.

23 Tahoe Duramax 3.0 4x4 LS with 10-speed AT with 49,500 miles.
Carwash damaged/cut my front tire and scratched the wheel. I had purchased a new Chevrolet OEM takeoff rim on eBay and 4 new Michelin Primacy LTX tires.

After tire and wheel install, I have noticed a vibration strictly during 68-73MPH (that is felt as buffeting like rear windows are open). I had taken the car back to the install shop, they roadforce it on the Hunter machine, one tire was pretty close to be out of range, Tirerack replaced the tire. Installed and re-balanced at another tireshop, they confirmed that all tires were within spec, however vibrations were still there. Took it to the dealer, paid for the re-balance and rotation.

Wanted to do a rotation to see if vibration will move from back to the the steering wheel on the front, but - same vibration/buffeting. Chevy dealer says it is not very likely the tires or rims are the problem (dealer himself does not of course reproduce the problem, because they cannot testdrive at 68-73MPH).

Additional thoughts:
-very narrow range strictly 68-73MPH
-rotation does not seem to change anything
-3 different tireshops does not seem to think the tires are the problem, but not sure if I need high quality $#4 who can validate if rims are not out of true or something with the wheel(s)
-maybe I am dreaming (not certain) but I am sensing this buffeting more when coasting (foot off the accelerator)
-lastly, if I am going through a corner in this speed (68-73MPH), I also feel even more

My hypothesis:
1) torque converter shudder, I am planning to do pan drop/drain/filter/fill on A/T.
2) takeoff rim causing the problem but balancing machines are not detecting rim problems (this is farfetched in my mind but I am not an expert on balancers if they can detect out of true or general rim issues)

Appreciate the thoughts.

 

[oil is slippery]

Hope the wisdom of the crowd will help me troubleshoot further. I am stumped. This truck was one of the smoothest riding highway cruisers, zero vibrations for 49,000 miles of any kind up until recent episode.

23 Tahoe Duramax 3.0 4x4 LS with 10-speed AT with 49,500 miles.
Carwash damaged/cut my front tire and scratched the wheel. I had purchased a new Chevrolet OEM takeoff rim on eBay and 4 new Michelin Primacy LTX tires.

After tire and wheel install, I have noticed a vibration strictly during 68-73MPH (that is felt as buffeting like rear windows are open). I had taken the car back to the install shop, they roadforce it on the Hunter machine, one tire was pretty close to be out of range, Tirerack replaced the tire. Installed and re-balanced at another tireshop, they confirmed that all tires were within spec, however vibrations were still there. Took it to the dealer, paid for the re-balance and rotation.

Wanted to do a rotation to see if vibration will move from back to the the steering wheel on the front, but - same vibration/buffeting. Chevy dealer says it is not very likely the tires or rims are the problem (dealer himself does not of course reproduce the problem, because they cannot testdrive at 68-73MPH).

Additional thoughts:
-very narrow range strictly 68-73MPH
-rotation does not seem to change anything
-3 different tireshops does not seem to think the tires are the problem, but not sure if I need high quality $#4 who can validate if rims are not out of true or something with the wheel(s)
-maybe I am dreaming (not certain) but I am sensing this buffeting more when coasting (foot off the accelerator)
-lastly, if I am going through a corner in this speed (68-73MPH), I also feel even more

My hypothesis:
1) torque converter shudder, I am planning to do pan drop/drain/filter/fill on A/T.
2) takeoff rim causing the problem but balancing machines are not detecting rim problems (this is farfetched in my mind but I am not an expert on balancers if they can detect out of true or general rim issues)

Appreciate the thoughts.

Do you have a spare that you can temporarily replace the new to you wheel with? Could narrow down where the problem might be.

 

[CleanSump]

Get the new (junkyard) wheel off and see what happens.

 

[CapriRacer]

Additional thoughts:
-very narrow range strictly 68-73MPH

Wheel end vibrations are usually in the 50 to 70 mph range, so this is almost outside the range.

-rotation does not seem to change anything

This sounds like "Not Tires", something in the vehicle.

-3 different tireshops does not seem to think the tires are the problem, but not sure if I need high quality $#4 who can validate if rims are not out of true or something with the wheel(s)

You've had the tires road forced and replaced one that was suspect and no change. That would seem to point to something in the vehicle.

-maybe I am dreaming (not certain) but I am sensing this buffeting more when coasting (foot off the accelerator)
-lastly, if I am going through a corner in this speed (68-73MPH), I also feel even more

That sounds like a bad u-joint or a wheel bearing.

My hypothesis:
1) torque converter shudder, I am planning to do pan drop/drain/filter/fill on A/T.

Possible.

2) takeoff rim causing the problem but balancing machines are not detecting rim problems (this is farfetched in my mind but I am not an expert on balancers if they can detect out of true or general rim issues)

Unlikely. If that were true, rotating the tires should have changed things. Beside Road Force would generally show up an issue, even a runout issue!

You replaced the tires with new Michelins, which are not generally known for causing vibrations - another indicator, it's not tires/wheels.

My vote is for a wheel bearing that went bad because of what happened at the car wash.

Let us know what you find out.

 

[smokey_2020]

@CapriRacer much appreciated! I will take it back to the dealer to get them to check the bearings and u-joints. Will change the AT oil/filter tomorrow if no change back to the dealer. I am out of bumper to bumper so they should be excited to charge me for the bearings/u-joints

 

[CleanSump]

Please come back and let us know what goes down!

 

[smokey_2020]

@CleanSump, oh I will, I believe if my journey can help others, I am a happy camper. I have been working on my own cars as a DIY weekender for 35+ years and I do think that this one is not an obvious one, so will start from the simple A/T drain and fill and then will move to the wheel bearings and u-joints.

 

[OX1]

Have you tried going on a long highway trip. Immediately removing all 4 wheels and tires and taking to balance shop.
The only tires I own that don't flat spot, to varying degrees, depending upon type, aspect ratio (sticky low profile tires being the worst), and/or how long they sit), are the 70$ crappy 14's on my 59 bird and oddly enough, the original CUP 2's on my GT500.

The PS4S's on my 17 Fusion flat spot really bad, same for the drag radials I've had.
Usually tires with larger height sidewalls, and/or non perf tires flat spot less.
Still something to try. If they are being balanced with even a minor flat spot,
they will never be right.

 

[Dr Oldz]

Few things to look at.

1 Did the noise cancelling on your sound system get adjusted?
2 Check tire roundness
3 Possible driveshaft issue.
4 Possible the harmonics from the tires are what you are noticing.

 

[smokey_2020]

Few things to look at.

1 Did the noise cancelling on your sound system get adjusted?
2 Check tire roundness
3 Possible driveshaft issue.
4 Possible the harmonics from the tires are what you are noticing.

Thanks!
1. My LS does not have noise cancellation, lowest end trim.
2. Advice on how to check them? Tireshops checked them on balancers but I am not sure if balancers show out of round or not? I asked shops and they were mysterious about whether balancers see out of round or not
3. I did not feel anything at all until tires and rim change.
4. Feels like harmonics, but previous same brand same model tires did not have any at all, how one proves tire harmonics?

 

[Dr Oldz]

Thanks!
1. My LS does not have noise cancellation, lowest end trim.
2. Advice on how to check them? Tireshops checked them on balancers but I am not sure if balancers show out of round or not? I asked shops and they were mysterious about whether balancers see out of round or not
3. I did not feel anything at all until tires and rim change.
4. Feels like harmonics, but previous same brand same model tires did not have any at all, how one proves tire harmonics?

1 was a try…
2 jack vehicle, use a solid square object object u can get close to the tire treads and spin the tire to look for out of round. Wouldn’t hurt to put a dial indicator on the rims also. (Perhaps your new rim came bent)
3. Going back to the cause…the car wash, it it possible a steering or suspension part got damaged?
4.unfortunately by changing the tires.


Hope you get this figured out!

 

[OX1]

RF balancer can measure tire runout, but that is under the 1400 lb force.
I have not seen a specific way to measure runout, not under load with that machine.
(.009 inch is tire runout below).........

As suggested, I've also used a piece of wood, set up to rest on a balancer
right off the tire surface, while spinning. My original Hunter balancer was a smaller unit
with no hood. Many machine's won't spin without hood closed. You could rotate
tire by hand if that is the case. I guess worse case, you could even do it with tire/wheel
on the car.

http://luxjo.supermotors.net/MISC TRUCK-PARTS PICS/TOOLS/BALANCER/9712/ESCAPE/20230709_130830.mp4

If you want to get fancier without a RF machine, you can also use a magnetic mount,
cheap digital dial indicator, and small flat adapter on end of dial indicator, but you
need to find a spot on tire that has continuous tread all the way around.

http://luxjo.supermotors.net/MISC TRUCK-PARTS PICS/TOOLS/BALANCER/9712/ESCAPE/20230710_121946.mp4

One other thing to check is centering cones they are using. Quite a few modern rims don't seem to center well
with older, higher angle cones.

This set of "low angle" cones came with the used RF machine I got. Each cone only covers a small range of center
diameters, but they center the rim on the balancer machine much easier (more accurately), You do need a lot of those
cones to cover a wide range of rim hub-centric, internal diameters.

 

[Sequoiasoon]

I think you might want to find a different shop also. My bent rims, rim runout and tire runout were very easy to see on the balancers.

Just because a place has a road force balancer does not mean they will use it correctly or allocate the time to diagnose it correctly, IF it is the rims/tires.

One of the magnetic runout dials may help. You may find that there is rust on the seating surface inside/or outside the rotor/drum that manifested while they worked on the rest. They may need to be removed and rotated to a different spot based on runout, same with the rim.

Way back thread on TundraSolutions user had balance issues. Shop explained that even with roadforce the rims were "too round" to accomodate the tire issues. The actual as I recall was the the factory hubcentric rims were very true and balanced so no matter how you tried the lesser quality tire, it would never correct the tire imbalance. Your new/used rim may have a balance issue which may need the tires off to check them first.

After all that, just recently my son on his 195k+ mile 2010 Forte did have a bad CV joint. That caused vibrations and a wind buffeting sound randomly until it wasn't as random not long after.

 

[JohnnyG]

69 to 73 vibrations are almost always tire related. Check for belt separation in the tread area. Had a tire go bad like that once, it would spin balance fine (not road force) but shake your teeth out on the highway.

 

[JohnnyG]

Sometimes the road force part of the RFB is done at low speed....very low speed. The defect I'm referring to doesn't even start until higher speeds are reached.

 

[OX1]

I think you might want to find a different shop also. My bent rims, rim runout and tire runout were very easy to see on the balancers.

Just because a place has a road force balancer does not mean they will use it correctly or allocate the time to diagnose it correctly, IF it is the rims/tires.

One of the magnetic runout dials may help. You may find that there is rust on the seating surface inside/or outside the rotor/drum that manifested while they worked on the rest. They may need to be removed and rotated to a different spot based on runout, same with the rim.

Way back thread on TundraSolutions user had balance issues. Shop explained that even with roadforce the rims were "too round" to accomodate the tire issues. The actual as I recall was the the factory hubcentric rims were very true and balanced so no matter how you tried the lesser quality tire, it would never correct the tire imbalance. Your new/used rim may have a balance issue which may need the tires off to check them first.

After all that, just recently my son on his 195k+ mile 2010 Forte did have a bad CV joint. That caused vibrations and a wind buffeting sound randomly until it wasn't as random not long after.

Very true. Not a simple 5 minute procedure, if you do it correctly, starting with a bare rim.
Even the newer RF balancers that show them using a laser on external diameter of wheel,
say in the instructions, that if it does not work using laser, take tire off and do it the "old way".
Mic-ing bead mounting surface of wheel.

I finally got one as I was getting a decent amount of tires, that balanced out pretty well,
but were not uniform and/or even round, many times (even though rims
usually mic'd out close to perfect).

Also true, if wheels are perfect, RF procedure cannot be accomplished in the
traditional sense. But it can tell you your brand new tire, was just not made right,
(which as mentioned, is why I finally got mine).

I send back a decent amount of tires now. Why should I accept tires that are
really bad or even just OK. My brand new F250 had tires RF'ing 55-60
(and Ford wouldn't or couldn't fix it). I managed to find two that were 8 and 11.
Same exact brand/size tire, same rims...

I try to keep my RF numbers below 15 on perf tires, and below 20 on LT's.

 

[OX1]

Sometimes the road force part of the RFB is done at low speed....very low speed. The defect I'm referring to doesn't even start until higher speeds are reached.

Pretty much every modern balancer spins 300 RPM or less (or about 30 MPH on a 275/70R18 lets say).
Not sure on the RF part especially, speed even matters that much. It's checking runout, due to changes in
tire spring rate, around the tire.

Anyway, it works. This is my 23 F250 brand new. (RF 55-60). Elbow leaning on center console.

http://luxjo.supermotors.net/23 F250 SD/TIRES/VIBRATION/20230718_083343.mp4

RFing 8/11 front, 18/22 rear

http://luxjo.supermotors.net/23 F250 SD/TIRES/AFTER ROAD FORCE/20230805_085317.mp4

 

[smokey_2020]

Thanks guys, I have drained, filter changed and refilled transmission today. Got done later than expected. Will test tomorrow. I doubt that torque converter shudder is the problem but will update.
Next will be looking for a good tire shop near Asheville NC who can help me work through this. Local GMC dealer has Hunter Elite machine and gave me an appointment, perhaps they can check u-joints and bearings.

 

[smokey_2020]

Drove a bit with new oil in the transmission, do not think it was torque converter shudder, or at least transmission oil drain/fill did not eliminate the vibration at 68-73.
Will try to find a shop to check rims for lateral play and to check wheel bearings/CV joints.

 

[OX1]

One other thing you could have them check if they will do it.
If it has a 4WD mode (not auto) and you can turn off traction control.
Run all 4 wheels/tires mounted on the vehicle, up on a lift,
just for a visual inspection (if you only have an "auto mode" or
no selectable TC, it might go crazy thinking your are massively slipping)

I don't really use shops for anything, so not sure if many would do that
these days, liability and all........... (but back in the day when I worked at a shop,
we would do that here and there, even to inspect driveshafts "at speed"......)