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Posted

The update I have on my truck today is not a good one. The dealer called and said the vibration is "better". They loosened all motor, tranny, exhaust mounts and torqued them all back down. Then the genius field engineer decided to balance my new driveshaft with hose clamps. Is this really the best thing their engineers can come up with?

Now that's classy, real classy. And the worst part is that they're not even embarrassed to admit to it.

Posted

 

 

 

Don't hold back Jesse, tell them how you really feel LOL

If I was posting how I really feel I'd get kicked off of Facebook, and here lol

Posted

I went to the dealer today to check out my truck and test drive it and I have to say it rides a lot better on the highway but I expressed my concern on using hose clamps as a permanent fix for the driveshaft. They agreed to send it out to a local shop to have it balanced properly but didn't sound optimistic that the truck would drive the same once they put the shaft back on. I sincerely hope it does at this point. Makes me wonder how many other trucks they gave back to people with hose clamps as a fix. Not everybody knows how half ass that is!

  • Like 1
Posted

Hey all , new to this group. I bought a 2015 Silverado 1500 a month ago. I have 424 miles on it, 100 I have driven.

There is a vibration at 30-70 mph, first complaint they road forced balanced tires, found one out of spec, replaced it with a 2 year old tire, said all was fine. Stated to drive home and went back to the dealer and said the vibration is still there, took the service manager for a ride and he said they would do a PICO test on it. Test done, found the ring and pinion back lash was out 3000. Replaced the ring and pinion, still a vibration. Service manager says it normal, and not to worry about it. Took the truck home, drove to work the next day, went to the dealer for a recheck, the GM rep drove it, said its normal. I also drove a new 2016, GMC 1500 2015, 2015 w/18 inch wheels, and a z71, all had the same issues, maybe normal for most but I don't want it any more. Anyone else had the same problem? Cant understand why GM wants all customers of the Silverado,s and sierras to live with the vibration, normal for v8 to v4,

I don't feel that issue, feel it all the time. Sorry cant pay for issues they cant fix, They admit theres a issue, but only have a go so far to fix the customers complaints.

So, as of the other day they will let me have what is call an enhanced trade, not sure how much I will get off another truck. Drove a 2016 yesterday w/18s, little to no vibration, waiting to see what the bottom line will be, they said they would not cover the ziebart rust protection. They sue move slow.

Posted (edited)

Hey all , new to this group. I bought a 2015 Silverado 1500 a month ago. I have 424 miles on it, 100 I have driven.

There is a vibration at 30-70 mph, first complaint they road forced balanced tires, found one out of spec, replaced it with a 2 year old tire, said all was fine. Stated to drive home and went back to the dealer and said the vibration is still there, took the service manager for a ride and he said they would do a PICO test on it. Test done, found the ring and pinion back lash was out 3000. Replaced the ring and pinion, still a vibration. Service manager says it normal, and not to worry about it. Took the truck home, drove to work the next day, went to the dealer for a recheck, the GM rep drove it, said its normal. I also drove a new 2016, GMC 1500 2015, 2015 w/18 inch wheels, and a z71, all had the same issues, maybe normal for most but I don't want it any more. Anyone else had the same problem? Cant understand why GM wants all customers of the Silverado,s and sierras to live with the vibration, normal for v8 to v4,

I don't feel that issue, feel it all the time. Sorry cant pay for issues they cant fix, They admit theres a issue, but only have a go so far to fix the customers complaints.

So, as of the other day they will let me have what is call an enhanced trade, not sure how much I will get off another truck. Drove a 2016 yesterday w/18s, little to no vibration, waiting to see what the bottom line will be, they said they would not cover the ziebart rust protection. They sue move slow.

You should go for an "enhanced" buyback instead. Unless you like the way these trucks vibrate. And don't expect someone who tells you that it is "normal" to fix it. How do you know the new one will not start vibrating after a few hundred miles even if it does not vibrate during the test drive?

 

And the gear backlash can be adjusted. So if it is out of spec, it does not require replacement of ring and pinion gears unless there is something wrong with the gears themselves, or some unacceptable wear pattern is evident, which I consider very unlikely with a few hundred miles on the truck. It looks like they replaced the gears just to make it look like they are addressing the problem. And how do you know that they adjusted the gear backlash and gear contact pattern properly? Did they show you in writing what they adjusted it to and what the allowable GM backlash spec is? Might as well replace both of your headlights if they are aimed incorrectly.

Edited by pm26
  • Like 1
Posted

 

pinion shaft to driveshaft angle issues will change with vehicle speed/tire speed not engine speed. the drive shaft is always spinning approximately 3 times the speed of the tires.

 

depending what gear the transmission is in will determine the engine speed for a given vehicle speed.

 

you can do 70mph in 5th or 6th. the engine speed will be very different. however the tire rpms and drive shaft rpms will be the same at 70mph in 5th as they are at 70mph in 6th.

The PICO scope is not some magical box like the dealer is making it out to be, it's just an accelerometer with some software running over the top of it that takes the frequency detected and relates that frequency to whatever part matches that frequency at a particular speed. How it works: The typical tire on these trucks is about 32" tall. It takes 630 rotations for the tire to travel the distance of 1 mile. So at 70 mph the tire is spinning at about 735 rpm. 70 x 635 = 44450 rotations per hour divided by 60 minutes per hour. To convert to hertz which is cycles per second just divide by 60 again and you have the tire angular velocity of 12.25 Hz. So like Laf7337 said regardless of input from the motor or transmission the tire rotates at 12.25 rotations per second at 70 mph. So GM puts a PICO scope on the truck and detects a 12.25 Hz vibration instead of the scope saying there's a 12.25 hz vibration the software deduces its a tire. However the imbalance can be the hubs, brake rotors, axle shafts, ring gear or anything else rotating at the same speed. The scope really has no idea which component is bad. So for a driveline vibration at 70 mph multiply 12.25 Hz by the rear end ratio say it's a 3.42, 12.25 x 3.42 the vibration would be approximately 42 Hz. PICO scope detects a 42 Hz vibration and says drive line, could be a simple balance problem, or it could be a bad pinion, bad pinion flange, bad working angles in the case of a 4x4 a bad output stub shaft on the t-case, again the PICO scope doesn't know. The dealer doesn't know and starts throwing parts on in the general problem area. So many parts could cause the issue or be causing the issue in combination with one another. Everyone mentions the dealer putting the PICO on their truck and detecting vibration but few to none ever get fixed. F*c< GM, their PICO scope, their shitty engineering and their unwillingness to be forthcoming with the issues and fix them.

  • Like 4
Posted

The PICO scope is not some magical box like the dealer is making it out to be, it's just an accelerometer with some software running over the top of it that takes the frequency detected and relates that frequency to whatever part matches that frequency at a particular speed. How it works: The typical tire on these trucks is about 32" tall. It takes 630 rotations for the tire to travel the distance of 1 mile. So at 70 mph the tire is spinning at about 735 rpm. 70 x 635 = 44450 rotations per hour divided by 60 minutes per hour. To convert to hertz which is cycles per second just divide by 60 again and you have the tire angular velocity of 12.25 Hz. So like Laf7337 said regardless of input from the motor or transmission the tire rotates at 12.25 rotations per second at 70 mph. So GM puts a PICO scope on the truck and detects a 12.25 Hz vibration instead of the scope saying there's a 12.25 hz vibration the software deduces its a tire. However the imbalance can be the hubs, brake rotors, axle shafts, ring gear or anything else rotating at the same speed. The scope really has no idea which component is bad. So for a driveline vibration at 70 mph multiply 12.25 Hz by the rear end ratio say it's a 3.42, 12.25 x 3.42 the vibration would be approximately 42 Hz. PICO scope detects a 42 Hz vibration and says drive line, could be a simple balance problem, or it could be a bad pinion, bad pinion flange, bad working angles in the case of a 4x4 a bad output stub shaft on the t-case, again the PICO scope doesn't know. The dealer doesn't know and starts throwing parts on in the general problem area. So many parts could cause the issue or be causing the issue in combination with one another. Everyone mentions the dealer putting the PICO on their truck and detecting vibration but few to none ever get fixed. F*c< GM, their PICO scope, their shitty engineering and their unwillingness to be forthcoming with the issues and fix them.

 

Great explaination. We use the same thing on turbine engines. Like you said, every part has it own RPM, frequency etc. So it's pretty easy to nail down a bad bearing etc.

Someone ought to start a speadsheet on this vibration problem, What year models, what type tires, 2 wheel, 4 wheel, crew cab long bed or short bed, see if there is common bond.

My truck is 2015 2500 4 x 4 long 8 ft. bed 4 door Sierra and I have absolutely NO vibration what so ever. Best truck I've ever owned and I've had Fords, Chevy's and Dodges.

  • Like 2
Posted

A while ago I started chasing down editors/writers at top auto rags and publications to try and get some traction on these issues. I also created a Facebook group as an alternative source for information.

 

It finally looks like at least one automobile publication is going to be writing a story about these issues. I just got word that the news editor for a auto rag (can't say just yet) is "finalizing his story on the SUV issues" and asked for more information. I hope this is the bump we need to get GM to get off of their ass and do something. I will keep you all posted. FYI, I have a 2016 Yukon XL Denali with buffeting issues but also with the terrible vibration issues that you guys are experiencing as well.

 

 

UPDATE: I spoke to Stephen Elmer, News Editor for Autoguide.com, this morning. They are days away from publishing a piece on our issues. He is now on these forums and has reviewed a lot (not sure if he hit all 458 pages). GM has provided comments back to him basically stating that a PI was issued for the buffeting (for the Yukon/Suburban/Escalade line) and that should have fixed it. It obviously didn't. Regarding the larger vibration issue, dealers are obviously trying all types of things none of which are really working. We are trying to get more attention on this and this is a great start. I've asked him to chime in and ask any specific questions that he can include in his piece. This will hopefully get us closer to a fix.

 

Stephen, please quote this message as a starting point. Thanks.

  • Like 2
Posted

The PICO scope is not some magical box like the dealer is making it out to be, it's just an accelerometer with some software running over the top of it that takes the frequency detected and relates that frequency to whatever part matches that frequency at a particular speed. How it works: The typical tire on these trucks is about 32" tall. It takes 630 rotations for the tire to travel the distance of 1 mile. So at 70 mph the tire is spinning at about 735 rpm. 70 x 635 = 44450 rotations per hour divided by 60 minutes per hour. To convert to hertz which is cycles per second just divide by 60 again and you have the tire angular velocity of 12.25 Hz. So like Laf7337 said regardless of input from the motor or transmission the tire rotates at 12.25 rotations per second at 70 mph. So GM puts a PICO scope on the truck and detects a 12.25 Hz vibration instead of the scope saying there's a 12.25 hz vibration the software deduces its a tire. However the imbalance can be the hubs, brake rotors, axle shafts, ring gear or anything else rotating at the same speed. The scope really has no idea which component is bad. So for a driveline vibration at 70 mph multiply 12.25 Hz by the rear end ratio say it's a 3.42, 12.25 x 3.42 the vibration would be approximately 42 Hz. PICO scope detects a 42 Hz vibration and says drive line, could be a simple balance problem, or it could be a bad pinion, bad pinion flange, bad working angles in the case of a 4x4 a bad output stub shaft on the t-case, again the PICO scope doesn't know. The dealer doesn't know and starts throwing parts on in the general problem area. So many parts could cause the issue or be causing the issue in combination with one another. Everyone mentions the dealer putting the PICO on their truck and detecting vibration but few to none ever get fixed. F*c< GM, their PICO scope, their shitty engineering and their unwillingness to be forthcoming with the issues and fix them.

 

Couln't have said it better. Even service writers and some managers tink the Pico scope is some miracle machine that just tells a tech whats wrong.

Posted

No vibs in mine (yet). With so many replies and views you would think someone would come up with a fix! There are smart people at GM that is why they don't have a fix.It would cost GM a boatload of $$$$.Cut their own throats.Now .. Maybe...If .... We if we had a reward of some sort it would up the Annie. Someone knows, they are not telling. ..Maybe start with a vib truck and start stripping her down and adding custom replacement parts until the vibs stopped!...Got any ideas????... Read one post where the truck didn't vib after being jacked up and wheels R +R. Let's figure this out. Think! Think! I have been. Someone be a Hero for this topic!

Second time
Posted

Hey all , new to this group. I bought a 2015 Silverado 1500 a month ago. I have 424 miles on it, 100 I have driven.

There is a vibration at 30-70 mph, first complaint they road forced balanced tires, found one out of spec, replaced it with a 2 year old tire, said all was fine. Stated to drive home and went back to the dealer and said the vibration is still there, took the service manager for a ride and he said they would do a PICO test on it. Test done, found the ring and pinion back lash was out 3000. Replaced the ring and pinion, still a vibration. Service manager says it normal, and not to worry about it. Took the truck home, drove to work the next day, went to the dealer for a recheck, the GM rep drove it, said its normal. I also drove a new 2016, GMC 1500 2015, 2015 w/18 inch wheels, and a z71, all had the same issues, maybe normal for most but I don't want it any more. Anyone else had the same problem? Cant understand why GM wants all customers of the Silverado,s and sierras to live with the vibration, normal for v8 to v4,

I don't feel that issue, feel it all the time. Sorry cant pay for issues they cant fix, They admit theres a issue, but only have a go so far to fix the customers complaints.

So, as of the other day they will let me have what is call an enhanced trade, not sure how much I will get off another truck. Drove a 2016 yesterday w/18s, little to no vibration, waiting to see what the bottom line will be, they said they would not cover the ziebart rust protection. They sue move slow.

Went to drive another truck at the dealership, ended up driving 7 2015s various options. All had vibrations. Looked a 2016 w/18s a/t very little vibration, told the dealership to find out what if any the difference would be. not sure if they made adjustments on the assembly line or its a hit or miss with the 2016. I don't want to send any more money to get another truck. So I am waiting to hear form the GM Rep.

Posted

 

Someone ought to start a speadsheet on this vibration problem, What year models, what type tires, 2 wheel, 4 wheel, crew cab long bed or short bed, see if there is common bond.

My truck is 2015 2500 4 x 4 long 8 ft. bed 4 door Sierra and I have absolutely NO vibration what so ever. Best truck I've ever owned and I've had Fords, Chevy's and Dodges.

 

I could whip up an online form that could help us paint a picture. A quick online survey where the link could be shared and everyone could see the results. The next question then is, what information would be relevant/useful? What do y'all think of this:

 

  • Model Year [2015 or 2016]
  • Model [silverado or Silverado HD or Sierra or Sierra HD or Tahoe or Yukon or Escalade or Suburban or Yukon XL or Escalade ESV]
  • Pickup Wheelbase [regular or extended or crew]
  • Engine [4.3L or 5.3L or 6.2L or 6.0L or 6.6L]
  • Drivetrain [2wd or 4wd]
  • Wheel Size [18" or 20" or 22" or other]
  • Last 6 characters of VIN [textbox]
  • problem [vibration and/or buffeting and/or booming or none]
  • has reported to GM dealership [yes or no]
  • note [free form text box]
  • Like 3
Posted

 

pinion shaft to driveshaft angle issues will change with vehicle speed/tire speed not engine speed. the drive shaft is always spinning approximately 3 times the speed of the tires.

 

depending what gear the transmission is in will determine the engine speed for a given vehicle speed.

 

you can do 70mph in 5th or 6th. the engine speed will be very different. however the tire rpms and drive shaft rpms will be the same at 70mph in 5th as they are at 70mph in 6th.

Yes,

 

i forgot to add that the driveshaft speed will be the engine speed divided by transmission gear ratio for each gear. If that happens to be 1:1 (the top gear on some auto transmissions), then it is the same as speed of the engine.

Posted

<p>

 

 

I could whip up an online form that could help us paint a picture. A quick online survey where the link could be shared and everyone could see the results. The next question then is, what information would be relevant/useful? What do y'all think of this:

 

  • Model Year [2015 or 2016]
  • Model [silverado or Silverado HD or Sierra or Sierra HD or Tahoe or Yukon or Escalade or Suburban or Yukon XL or Escalade ESV]
  • Pickup Wheelbase [regular or extended or crew]
  • Engine [4.3L or 5.3L or 6.2L or 6.0L or 6.6L]
  • Drivetrain [2wd or 4wd]
  • Wheel Size [18" or 20" or 22" or other]
  • Last 6 characters of VIN [textbox]
  • problem [vibration and/or buffeting and/or booming or none]
  • has reported to GM dealership [yes or no]
  • note [free form text box]

<p>

 

 

I could whip up an online form that could help us paint a picture. A quick online survey where the link could be shared and everyone could see the results. The next question then is, what information would be relevant/useful? What do y'all think of this:

 

  • Model Year [2015 or 2016]
  • Model [silverado or Silverado HD or Sierra or Sierra HD or Tahoe or Yukon or Escalade or Suburban or Yukon XL or Escalade ESV]
  • Pickup Wheelbase [regular or extended or crew]
  • Engine [4.3L or 5.3L or 6.2L or 6.0L or 6.6L]
  • Drivetrain [2wd or 4wd]
  • Wheel Size [18" or 20" or 22" or other]
  • Last 6 characters of VIN [textbox]
  • problem [vibration and/or buffeting and/or booming or none]
  • has reported to GM dealership [yes or no]
  • note [free form text box]

<p>

 

 

I could whip up an online form that could help us paint a picture. A quick online survey where the link could be shared and everyone could see the results. The next question then is, what information would be relevant/useful? What do y'all think of this:

 

  • Model Year [2015 or 2016]
  • Model [silverado or Silverado HD or Sierra or Sierra HD or Tahoe or Yukon or Escalade or Suburban or Yukon XL or Escalade ESV]
  • Pickup Wheelbase [regular or extended or crew]
  • Engine [4.3L or 5.3L or 6.2L or 6.0L or 6.6L]
  • Drivetrain [2wd or 4wd]
  • Wheel Size [18" or 20" or 22" or other]
  • Last 6 characters of VIN [textbox]
  • problem [vibration and/or buffeting and/or booming or none]
  • has reported to GM dealership [yes or no]
  • note [free form text box]
Posted (edited)

You know one thing I noticed the other day when I was sitting at a light and slightly moving forward with my foot still a little on the brake I could feel like a pulse in the truck like the anti-lock braking was hitting back and forth. Do you think that maybe something like this could be happening at higher speeds and making the vibration. I also have the vibration in my 2015 double cab 5.3ltr. Sierra. Just a thought. I even could make it happen in a parking lot. Maybe they could try disabling the anti-lock system and see if it makes a difference.

Edited by rshad

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