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Posted

SMC, I have the center console vibration. I feel more of the vibration in the seats than the steering wheel. Where did you feel the vibration the most? You would think front hub would vibe steering wheel? Or was it felt in the butt? I can feel the slight vibes manageable to 70 to 74, anything above that vibes really bad.

If I could afford it I would get myself another Cummins. Or i would buy a Tundra.

 

Sent from my SM-N930V using Tapatalk

Posted

My friend has a 2016 2500 Cummins Megacab, loaded, 67k sticker. He got it up to 65 the other day and the thing shook like crazy. Much worse than any of these videos in here. My guess is its the frames on these trucks that don't damper any of the vibrations.

Posted

thats

 

My friend has a 2016 2500 Cummins Megacab, loaded, 67k sticker. He got it up to 65 the other day and the thing shook like crazy. Much worse than any of these videos in here. My guess is its the frames on these trucks that don't damper any of the vibrations.

part of the problem. They transfer all harmonics into the cab

Posted (edited)
1956

After a Transmission failure, a A/C failure now the damned POS OnStar has failed... these efferes better get me freakin fixed up!! effing tired of these damned POS Chevrolets.

2004
Edited by scooter484
Posted (edited)

Time to start thinking outside the box since GM isn't and the same thing over and over is being tried by dealerships to no avail... I'm tired of reading about road force balances and driveshaft balance/replacements not fixing the problem. They've been trying the same thing for 3 years...what's the definition of insanity again?

 

I've got the 65-80 mph vibration. It starts faintly at 65, peaks at 75 and fades away to 80 and is fairly smooth after that, although it isn't perfect. I can feel it mostly in the floor/seat, and only a little bit in the steering wheel. The jump seat armrest shakes pretty bad, it will visibly shake a drink but I don't think it would spill it. I have a 2016 2WD CC SLE Sierra with the OEM 20" wheels and tires. The vibration occurs regardless of what gear the truck is in, neutral included, and V4 mode doesn't affect it either. In theory this means that there should be no issue with any drivetrain component in front of the diff. EDIT: this is wrong out of context. Driveshaft and diff components could also be the source, but these would be 2nd order vibrations. Below, I determine that I have a 1st order vibration so that rules these components out.)

 

I've used the VibSensor Android app to measure the frequency of the vibrations from 65-80 mph, meaning I've recorded multiple 60 second samples at various consistent speeds in that range. The tests all show a strong ~10-14Hz response depending on the speed. I've placed my phone on the armrest, floor, and dash with all similar results, the only change being the magnitude of the frequency. This frequency should point to a 1st order vibration.

 

With all of that said, we should be looking at all things that could cause a first order vibration regardless of engine speed. My gut tells me that the problem lies somewhere in the wheel assembly, although a side bearing, cup, or shim could be the issue. Even still, with as elusive as this problem has been, it could be an out of balance radio knob :P

 

To start diag of a 1st order vibration #PI1354C is actually the beginnings of a great bulletin, but for some reason GM stops diag and resolution after balancing the tires. Let's look at all the possible things that could cause a 1st order vibration below. Remember, runout can be radial or lateral.

  • Tire balance
  • Tire runout
  • Wheel runout
  • Tire uniformity/road force variation
  • Incorrect mounting
  • Rotor balance/runout (not warping)
  • Rear axle shaft/"hub" runout
  • Front hub runout
  • Wheel stud runout
  • Bearing runout

I'm sure there's potentially others, but that at least covers a lot more than a road force balance. The most efficient way to diag all of this at home is to simply measure the runout and go from there, that way we're not just throwing parts and money at the problem. The Hunter GSP9700 will take care of the first 5 things to a certain extent. Placement of the tire on the wheel can help with runout to a point, and the machine will also alert the technician if the wheel wasn't mounted correctly, although this doesn't help when actually mounting on the car. I don't have the tools or time to measure runout of the other components, but I'm considering tackling it if no one here can easily do it. I realize we'll need many samples though.

 

Once it has been confirmed that there isn't any excessive runout to any component, the other major vibration source is balance. The GSP9700 takes care of the wheels and tires which leaves the rotor as the only other thing that can be individually balanced (more on balancing the entire assembly as a whole later). Yes, there is such thing as balancing a rotor. No, I'm not talking about warping. Yes, I know that this is very uncommon. All reputable brake companies balance their rotors during manufacturing, however, I've come across many stories of OEM and even top aftermarket brake companies shipping extremely out of balance rotors. If GM's source has poor QA there could be many trucks with out of balance rotors. Find a machine shop that will check and balance your rotors.

 

Finally, if you still have a vibration after confirming that runout is within tolerances, the tires and rotors are balanced, and road force variation has been corrected...balancing the entire assembly as a whole should be the next step. All of the "fixes" above are just band-aids. There is no such thing as a perfectly balanced and perfectly round component. So the natural frequency of any individually balanced or "rounded" (runout within tolerance) component can be exacerbated when installed with all of the other imperfect components that make up the assembly. What I mean is that stud runout for example can actually make it appear as if you have wheel/tire runout and you'll feel the same vibrations as if your wheel/tire actually had that runout itself. If bad enough, you'll feel the vibration. (and if you have multiple components that are bad enough it could be that the result would be a much higher order vibration and harder to diagnose) To attempt to put a band-aid on this, there's two popular options: on car balancing or a dynamic balancing solution like what Centramatic offers. But again, you have to hope that the amount of runout is small enough that the balance can compensate for it, or hopefully it's a true balance issue that is correctable.

 

This entire theory also explains why there is such a wide variety of owners who have vibrations at different speeds and coming from different locations. smcgillis10 just recently fixed his vibration after replacing his drivers front hub assembly. My guess is he had bearing, stud, or hub runout that was bad enough any sort of balance never could fully compensate for it. This theory also requires that owners not read smcgillis10's solution and replace their drivers front hub assembly. That wouldn't do them any good if the out of spec component is in an assembly on any other other 3 wheels. Being that vibrations seem to be coming from the front or the rear, 2WD or 4WD, is another reason that I believe the issue must be coming from a wheel assembly component and not the driveshaft, transmission, pinion, u-joint, torque converter, or any of the other sources that are being looked at.

 

This was mostly me putting together my thoughts on the issue so that I can begin my own troubleshooting on my truck, but I hope that some of you find it useful, or that it sparks some new thoughts here other than the same thing over and over for 600+ pages. Also, please let me know if any of my logic above isn't sound or if you can expand on any of my thoughts.

 

Here are some links I referenced while putting together these thoughts:

Edited by slopra
  • Like 2
Posted (edited)

Hi everyone.... newb here, with the vibrating problem, starts about 72-74 mph and continues up to +80. Truck has a little over 800 miles on it.

Took my '16 Z71 ext. cab into the dealer yesterday, hung around for 2 hours while they did their thing. Man behind the counter comes out and told me they test drove it and did feel the vibe. Said they checked tire balance, steering, suspension, yada, and all is good. Said they adjusted tire pressure on all 4 to 35 lbs. Told me to take it home and call if there's a problem. So I'm think'n... IF there's a problem, wtf?!? Anyways, I took the scenic route home making it a point to get in about 15 miles of highway. As I fully expected the vibe was still there, starting at low 70s as usual.

 

So, when I got home I called them to let them know tire pressure adjustment didn't do the trick LOL. Service guy repeated what they had checked, and/but was nice about it. I also nicely responded letting him know and saying, it's a new truck and it should not vibrate and we/they gotta fix it. Service guy said to bring it in Wed of next week, and leave it for the day.

 

Granted, it's early in the game, but I don't have a real warm fuzzy feeling about this vibration issue. I'll report back as the saga continues.

Edited by Willyone
Posted

Silverado and Sierra Vibration Fix:

 

 

#1

 

 

#2

 

 

#3

 

 

#4

 

 

#5

 

 

 

I'm surprised they only have 5 lol

  • Like 2
Posted

Well a little over 5 months ago I send GM a final repair notice, they offered a trade assist and I have been fighting with them ever since on the value. I Spoke with the rep today and it appears that it has finally paid off. They have contacted the dealer to set up for me to get the new truck I picked out. Waiting on final approval of the new numbers for the value of my current truck. Hopefully within the next week or 2 I'll be out of my POS 2015 Silverado LT Crew 4x4 with the 4.3L V6 and into a 2017 Sierra Denali Crew 4x4 with the 6.2L V8.

 

glad its almost over.

Posted

Anyone else notice that a full tank of gas and slightly colder weather improved the vibration? I'm beginning to think that mine be related to the rear drive shaft, diff or pinion angle?

Posted

Anyone else notice that a full tank of gas and slightly colder weather improved the vibration? I'm beginning to think that mine be related to the rear drive shaft, diff or pinion angle?

yes, that was brought up last fall/winter. nothing came of it though

Posted

 

Time to start thinking outside the box since GM isn't and the same thing over and over is being tried by dealerships to no avail... I'm tired of reading about road force balances and driveshaft balance/replacements not fixing the problem. They've been trying the same thing for 3 years...what's the definition of insanity again?

 

I've got the 65-80 mph vibration. It starts faintly at 65, peaks at 75 and fades away to 80 and is fairly smooth after that, although it isn't perfect. I can feel it mostly in the floor/seat, and only a little bit in the steering wheel. The jump seat armrest shakes pretty bad, it will visibly shake a drink but I don't think it would spill it. I have a 2016 2WD CC SLE Sierra with the OEM 20" wheels and tires. The vibration occurs regardless of what gear the truck is in, neutral included, and V4 mode doesn't affect it either. In theory this means that there should be no issue with any drivetrain component in front of the diff. EDIT: this is wrong out of context. Driveshaft and diff components could also be the source, but these would be 2nd order vibrations. Below, I determine that I have a 1st order vibration so that rules these components out.)

 

I've used the VibSensor Android app to measure the frequency of the vibrations from 65-80 mph, meaning I've recorded multiple 60 second samples at various consistent speeds in that range. The tests all show a strong ~10-14Hz response depending on the speed. I've placed my phone on the armrest, floor, and dash with all similar results, the only change being the magnitude of the frequency. This frequency should point to a 1st order vibration.

 

With all of that said, we should be looking at all things that could cause a first order vibration regardless of engine speed. My gut tells me that the problem lies somewhere in the wheel assembly, although a side bearing, cup, or shim could be the issue. Even still, with as elusive as this problem has been, it could be an out of balance radio knob :P

 

To start diag of a 1st order vibration #PI1354C is actually the beginnings of a great bulletin, but for some reason GM stops diag and resolution after balancing the tires. Let's look at all the possible things that could cause a 1st order vibration below. Remember, runout can be radial or lateral.

  • Tire balance
  • Tire runout
  • Wheel runout
  • Tire uniformity/road force variation
  • Incorrect mounting
  • Rotor balance/runout (not warping)
  • Rear axle shaft/"hub" runout
  • Front hub runout
  • Wheel stud runout
  • Bearing runout

I'm sure there's potentially others, but that at least covers a lot more than a road force balance. The most efficient way to diag all of this at home is to simply measure the runout and go from there, that way we're not just throwing parts and money at the problem. The Hunter GSP9700 will take care of the first 5 things to a certain extent. Placement of the tire on the wheel can help with runout to a point, and the machine will also alert the technician if the wheel wasn't mounted correctly, although this doesn't help when actually mounting on the car. I don't have the tools or time to measure runout of the other components, but I'm considering tackling it if no one here can easily do it. I realize we'll need many samples though.

 

Once it has been confirmed that there isn't any excessive runout to any component, the other major vibration source is balance. The GSP9700 takes care of the wheels and tires which leaves the rotor as the only other thing that can be individually balanced (more on balancing the entire assembly as a whole later). Yes, there is such thing as balancing a rotor. No, I'm not talking about warping. Yes, I know that this is very uncommon. All reputable brake companies balance their rotors during manufacturing, however, I've come across many stories of OEM and even top aftermarket brake companies shipping extremely out of balance rotors. If GM's source has poor QA there could be many trucks with out of balance rotors. Find a machine shop that will check and balance your rotors.

 

Finally, if you still have a vibration after confirming that runout is within tolerances, the tires and rotors are balanced, and road force variation has been corrected...balancing the entire assembly as a whole should be the next step. All of the "fixes" above are just band-aids. There is no such thing as a perfectly balanced and perfectly round component. So the natural frequency of any individually balanced or "rounded" (runout within tolerance) component can be exacerbated when installed with all of the other imperfect components that make up the assembly. What I mean is that stud runout for example can actually make it appear as if you have wheel/tire runout and you'll feel the same vibrations as if your wheel/tire actually had that runout itself. If bad enough, you'll feel the vibration. (and if you have multiple components that are bad enough it could be that the result would be a much higher order vibration and harder to diagnose) To attempt to put a band-aid on this, there's two popular options: on car balancing or a dynamic balancing solution like what Centramatic offers. But again, you have to hope that the amount of runout is small enough that the balance can compensate for it, or hopefully it's a true balance issue that is correctable.

 

This entire theory also explains why there is such a wide variety of owners who have vibrations at different speeds and coming from different locations. smcgillis10 just recently fixed his vibration after replacing his drivers front hub assembly. My guess is he had bearing, stud, or hub runout that was bad enough any sort of balance never could fully compensate for it. This theory also requires that owners not read smcgillis10's solution and replace their drivers front hub assembly. That wouldn't do them any good if the out of spec component is in an assembly on any other other 3 wheels. Being that vibrations seem to be coming from the front or the rear, 2WD or 4WD, is another reason that I believe the issue must be coming from a wheel assembly component and not the driveshaft, transmission, pinion, u-joint, torque converter, or any of the other sources that are being looked at.

 

This was mostly me putting together my thoughts on the issue so that I can begin my own troubleshooting on my truck, but I hope that some of you find it useful, or that it sparks some new thoughts here other than the same thing over and over for 600+ pages. Also, please let me know if any of my logic above isn't sound or if you can expand on any of my thoughts.

 

Here are some links I referenced while putting together these thoughts:

 

Assuming wheel runout is acceptable, most of the other goodies can be runout checked from the rim outer face with a dial indicator. Wheel stud runout could be a simple Cad Drawing on mylar with center being the hub center.

Posted

I brought my 1 month old 16 Sierra to Royal GMC in Birmingham AL this evening.

I explained the issues I was having and jokingly called it the chevy shakes. The techs explained that this would take up to a week to diagnose but they are only allowed to give me a rental car for 5 days and requested I come back next week.

They did say several customers have come in for similar issues and on a couple occasions they had to deal with GM in regards to a buyback. I asked if I could bring to another GM dealer and they said that was fine.

Rode over to Hendrick Chevy in Hoover AL and the tech said he would rather I come ack tomorrow to get me a loaner lined up.

 

My question is do I need to be selective on which dealer to diagnose or will I have similar outcomes regardless of where I go?

The shake started when I left Laura GMC and got on the highway back to bama. At the time I had no idea this was an issue and if I did I would have taken it back and flown home. If this cant be fixed I would strongly prefer to just ditch the GM truck completely and get a Chevy SS so I don't get another shaker. (Would this be an option if I paid the difference in MSRP?)

Posted

I brought my 1 month old 16 Sierra to Royal GMC in Birmingham AL this evening.

I explained the issues I was having and jokingly called it the chevy shakes. The techs explained that this would take up to a week to diagnose but they are only allowed to give me a rental car for 5 days and requested I come back next week.

They did say several customers have come in for similar issues and on a couple occasions they had to deal with GM in regards to a buyback. I asked if I could bring to another GM dealer and they said that was fine.

Rode over to Hendrick Chevy in Hoover AL and the tech said he would rather I come ack tomorrow to get me a loaner lined up.

 

My question is do I need to be selective on which dealer to diagnose or will I have similar outcomes regardless of where I go?

The shake started when I left Laura GMC and got on the highway back to bama. At the time I had no idea this was an issue and if I did I would have taken it back and flown home. If this cant be fixed I would strongly prefer to just ditch the GM truck completely and get a Chevy SS so I don't get another shaker. (Would this be an option if I paid the difference in MSRP?)

If the dealer is actually willing to work on it an acknowledges the problem, you're off to a good start. You can even change servicing dealers in the middle if it if you like, or the dealer begins to refuse to work on it. You will have to meet the lemon law requirements and send them a "Final Repair Notice" before GM would be willing to do anything else as far as trade assist or buyback. As far as getting a car instead, you can ask, but they typically require you to stay with a similar vehicle.

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