Jump to content

Shake or Vibration Issues

Silver space ship
 Share

Recommended Posts

abominable z71 Enthusiast

abominable z71

Posted
Posted

You could have a square "hub" and would not do anything....as long as the Lugs are placed in appropriate positions off center anything past that is just material for strength. It could look like shark teeth too and would not effect anything............keep trying!

 

You could have a square "hub" and would not do anything....as long as the Lugs are placed in appropriate positions off center anything past that is just material for strength. It could look like shark teeth too and would not effect anything............keep trying!

That's incorrect The rotating mass of the hub would create an imbalance in this situation because the additional material on one side of the hub moves the center of gravity away from the center of the hub. It is true any shape even square can be balanced but only if the center of gravity is located on the axis of rotation.

  • Replies 12.9k
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

csckickass
csckickass

Well folks, I did it. After all the failed attempts at the Chevy dealer I traded it in for a 2015 Ram 1500 Larame. I have to agree with the other folks on here that have done the same thing, it was th

mafd2
mafd2

Apparently you and the other customer reps don't care. If you or GM would care y'all would put more effort in the matter. Just coming on the forum and stating the same repetitive posts and being a 3

DALaws
DALaws

Well I have some good news and bad news about my truck vibrations. Good news is that my truck has a significantly less vibration at speed. The bad news is my truck has significantly less vibration. Fo

Posted Images

pickmeup Enthusiast

pickmeup

Posted
Posted

I drive that section of new pavement 2 or 3 times a month and it does it every time . First time driving after repave wife and I both thought we were having a severe and sudden carrier bearing failure in the rear end. For some strange reason it makes them Bridgestone A/T tires sing and slight vibration in floorboard. We even drove it in her new Camry no tire singing but a very subtle vibration or more like a quiver felt in that too but nothing like truck.

mookdoc6 Senior Enthusiast

mookdoc6

Posted
Posted

That's incorrect The rotating mass of the hub would create an imbalance in this situation because the additional material on one side of the hub moves the center of gravity away from the center of the hub. It is true any shape even square can be balanced but only if the center of gravity is located on the axis of rotation.

You get the jest of it! I am not talking 3LBS mass here vs other side? Were talking insignificant differences. I would bet both of us would be shocked at how off/different they could be from one side to the other...........

abominable z71 Enthusiast

abominable z71

Posted
Posted

You get the jest of it! I am not talking 3LBS mass here vs other side? Were talking insignificant differences. I would bet both of us would be shocked at how off/different they could be from one side to the other...........

We are talking about parts turned in a CNC lathe, They shouldn't be off to the point you can see it with the naked eye. Regardless of the machining tolerance, the amount of mass is only a small part of the equation, rotational speed, natural frequency, and damping ratio all have to be accounted for to determine if a small unbalanced mass will cause an issue. Where the issue arises is when the natural frequency and the input frequency equal one another. This is resonance and the vibration amplitude is very large regardless of the mass value being 3 lbs or 3 grams.

xkvator Enthusiast

xkvator

Posted
Posted

 

 

so you switched from 2wd to 4wd while driving and that fixed it from vibrating ??

all I can tell you is, it was vibrating pretty bad on the turnpike...while I was off the turnpike, traveling between a few stores, I put it in and out of 4wd a few times at around 40 mph...when I headed back up the highway at 65 to 70 mph, the vibration wasn't there...

i'm ruling out tires, because I traveled at least 300 miles after the dealer service, and it was fine...

the reason that I thought about putting it in and out of 4wd was, that 1 of the recalls was for reprogramming something with the 4wd...

 

and like I said...never an ounce of vibration in almost 25,000 miles...

mookdoc6 Senior Enthusiast

mookdoc6

Posted
Posted

We are talking about parts turned in a CNC lathe, They shouldn't be off to the point you can see it with the naked eye. Regardless of the machining tolerance, the amount of mass is only a small part of the equation, rotational speed, natural frequency, and damping ratio all have to be accounted for to determine if a small unbalanced mass will cause an issue. Where the issue arises is when the natural frequency and the input frequency equal one another. This is resonance and the vibration amplitude is very large regardless of the mass value being 3 lbs or 3 grams.

Agreed, you should not be able to see it with naked eye. About the only thing I going in my life is I am not associated with this thread/vibes etc. The only thing I can say is, "when I first bought the truck and brought it home the kids and I were jumping up in down in the bed" I thought to myself this is the stiffest truck bed I have ever jumped in and it's 2wd no Z71 blah,blah plain old 1500 suspension. It would seem to me this truck is ridiculously FRAME STIFF and a goofy ass instantaneous v4-v8 switching engine that is NOT isolated 1 bit from the transient frequency of 75 mph driving. I mean it all sounds great on paper but there is much going on with this truck/engine/drivetrain etc.

 

Just like my wifes Nissan it's brakes were ****ed upon delivery and the second off the lot been complaining......Only response is they make noise sir yes, many of the brakes do, but no injuries or accidents occurred and Nissan is not going to replace parts on your vehicle just to replace parts? The next GM iteration of AFM is Dynamic Skip Fire and hopefully the RANDOM firing patterns i.e. one here, one there, two this side 3 that side of combustion firing patterns and not just a BANK of Cylinders all at one time? Who, knows if this beast rolls smooth it's a damn nice truck and I feel for the fellas dealing with this nonsense!

wuznme Enthusiast

wuznme

Posted
Posted

Not that this is the fix, more an FYI...

 

I can change the amount of vibration in my truck switching from 22's with street tires to 17's with Nitto G2 tires.

 

The same roads that vibrate the truck on 22's are like a freshly paved road with 17's

  • Like 1
silveradosid Senior Enthusiast

silveradosid

Posted
Posted

i tried 3 different sizes of tires and two sets of rims and it only change the speed of when the vibration starts but the vibration is still the same between 95 and 100 klms. it is like i was driving off and on rumble strips

powerhaulic Enthusiast

powerhaulic

Posted
Posted

Just finished a 4000mi trip, ny to Alabama to Florida back to NY

This is the smoothest most enjoyable vehicle I've driven

Granted I installed 4 Michelin's (Defenders) 275/20's when I took delivery. Because I know the good years are junk.

Average 22mpg running 70mph++

abominable z71 Enthusiast

abominable z71

Posted
Posted (edited)

http://gm.oemdtc.com/5197/shakevibration-in-steering-wheel-floor-seat-at-highway-speeds-on-smooth-roads-1998-2005-buick-cadillac-oldsmobile-pontiac

 

http://www.revbase.com/BBBMotor/TSb/DownloadPdf?id=195111

 

I think GM needs to fire their NVH department and start over. Apparently they have a tough time building anything that doesn't shake.

Edited by abominable z71
  • Like 2
daleone3 Enthusiast

daleone3

Posted
Posted

One of these vibration cases just went before the New Hampshire State arbitration board and it was denied due to the defect not being present at the time of testing. Additionally customers are being reminded that the new vehicle warranty states that slight noise vibration or other normal characteristics of a vehicle are not covered under the new vehicle warranty.

That is their way of saying if you own it you can keep it

 

 

Sent from my iPhone using Tapatalk

mookdoc6 Senior Enthusiast

mookdoc6

Posted
Posted

So I've done some redneck testing. And it appears that my drive line has a bend or something. What do you think?https://vimeo.com/194200154

 

Sent from my Pixel XL using Tapatalk

 

Looks suspect no doubt? janky is what I would call it

chevyloco Enthusiast

chevyloco

Posted
Posted

One of these vibration cases just went before the New Hampshire State arbitration board and it was denied due to the defect not being present at the time of testing. Additionally customers are being reminded that the new vehicle warranty states that slight noise vibration or other normal characteristics of a vehicle are not covered under the new vehicle warranty.

That is their way of saying if you own it you can keep it

 

 

Sent from my iPhone using Tapatalk

 

Here's the 2017 Chevy Cover your A$$ Vibration Warranty

 

Repairs Covered The warranty covers repairs to correct any vehicle defect, not slight noise, vibrations, or other normal characteristics of the vehicle due to materials or workmanship occurring during the warranty period. Needed repairs will be performed using new, remanufactured, or refurbished parts.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • Grumpy Bear
      Some Assembly is Required

      By Grumpy Bear · Posted

      Can it still be Assembled I?    Stribeck says that we need a certain amount of viscosity under conditions of load and velocity to prevent two surfaces of a know roughness from tearing each other asunder. And we have marketing trying to tell the masses that those two surfaced require less of that commodity due to more exact limits being placed on the same old clearances. We also know that there are limits to how hard something can before it becomes to brittle to be viable and to smooth to 'wet' the surface and that both of those conditions have been known and met since about the Second World War.    That viscosity value shook out at 10 centistokes at 212 F just under a hundred years ago.  Give this a look: [Anton Parr]     What is advertised is the Kinematic viscosity (mm2/s) or that which has been density adjusted but the value we are after is the dynamic viscosity (mPa.s) or true viscosity. You can see that this number is dependent on density thus base stock and temperature. You can also see that an SAE 30 doesn't reach that value in this example. However an SAE 30 that is at the upper end of the SAE 30 range; 12.5 cSt (mm2/s), might. 12.5 * .83 = 10.375 (mm2/s). If you could find an SAE 30 at the upper end these days.   Then there is the complication of viscosity modifiers or VII or VM, whatever you wish to call them. Polymers added to very thin base oils, perhaps 3 to 6 cP oils, that will meet the SAE *W30 spec at 'tested' shear rates and 100 C/212F  target temperature. So a polymer fortified base that is a fraction of the 10 cP requirement Stribeck insist upon.   This could be all well and good if those polymers didn't have two very problematic 'features'. They shear or loose viscosity both 1.) permanently and 2.) temporality. And they do both omitted in the advertised data with the distinct  purpose of deceiving the consumer of the actual operating state of the fluid. I've shown the example of Warren Oils COSTCO 10.91 cSt 5W30 formuation several times where the 100 C HTHS value is 6.9 cP!! That's the temporary shear down and with and SSI or shear stability index of 9.4 cSt. Note the intentional deception in using mixed units?    After a short while that 9.4 cSt oil has a viscosity corrected dynamic value of 7.8 cP. But as the SSI is still within the range of an SAE *W30 whose lower value is 9.3 cSt.    This allows them to continue to call this SAE 16 weight oil a 30 weight, the cake, and still meet the API requirements for fuel efficiency IMPROVEMENT mandated by the EPA. The eating of the cake. By the time you've worn out your motor doing the responsible thing by adhering to the warranty requirements, (the stick), you get deprived of the carrot, wear control. So sad, to bad.   So what can be done? Do I need actually say? [Anton Parr]       Even this must be monitored if the oil is on the low side and the VII an organic or you opt for a 0W40 with an even lighter base oil and more / higher MW VII. (Note the lower density of the 40 weight versus the SAE 30 mono-weight?)    There is another workaround. Temperature. An SAE *W30 run at a bulk temperature of between 180 and 195 F.    Being the belt and suspenders sort I am I do both. Run it cook and run it heavy.    In Part II I'll work the AW package. 
    • Atlas
      Wow I'm in a pickle. (Broke down truck) and a story.

      By Atlas · Posted

      So, do I go elbow-deep on this thing or list it for sale and play dumb? Seems to "runs good."   I'm about $1200 away from having: -a rebuilt injector ($300) -a new cat ($250) -a new cat back exhaust (OE style) ($300) -a new AC compressor ($200) -AC refrigerant charge ($150)   In theory, this should rectify the obvious detracting issues from its value and operability. Cold AC with a non-squeaking AC pulley both sounds and feels good. An exhaust that isn't cut/hacked in 17 different places and doesn't vibrate on a crossmember would make it sound and feel less janky. A working cat would help the stink, and will save the earth, but *if and only if* the fuel system is working properly, which would also address the intermittent "rich" CEL.   Heard a good one... CEL for "Rich condition" means you haven't spent enough money on the truck lately, and it's letting you know.   Rebuilding the injector would seem to be the most important part. Replacing the cat would be secondary. I don't think mine is plugged or overly restricted, but it might be a little restricted? I have no good way to tell other than seat of the pants feel. I hate the smell.   The current theory is I have a rich idle problem: A bad fuel pressure regulator, or a leaking injector(s) being the highest probabilities. I already replaced the FPR but that doesn't mean its replacement isn't also bad. It was a new part from Dorman, but the packaging looked like it had been sitting on a shelf for 20 years.   This is the (single) upstream O2 sensor shown at idle. I'm getting a lot of "rich" it seems. Sometimes it stays high like that and doesn't drop down. That makes me think it's processing injector leaks or a partially stuck open injector.     Other times it looks like this. Nice oscillations between rich and lean, which is what I think it should be. Under load and at speed, the oscillations are nice and tight and uniform looking, high and low.     Fuel trims suggest the PCM is compensating pretty hard at idle to pull fuel out. But it's not enough to trip a CEL. Something about slowing to a stop: brake vaccum booster, EGR, or the EVAP purge is delayed, or there's pooled fuel in the intake again that's draining into a cylinder is enough to set the CEL. Of course, in two days of driving, it hasn't set. I was hoping to actually look at the freeze-frame data when it sets. IAT is high because it's idling on an 83 degree day here.  
    • Another JR
      Gasser Subforum Has Been Quiet - - So, Regenerative Braking and Using L10

      By Another JR · Posted

      Have considered installing a DC to DC charger in your camper to replace your isolator?  
    • newdude
      Gas fill door

      By newdude · Posted

      Common failure.  You need to replace the fuel door housing.   The painted cover transfers over to the new housing.  To remove the old one there is 4 spots where you poke the plastic to release it.  
    • newdude
      Gasser Subforum Has Been Quiet - - So, Regenerative Braking and Using L10

      By newdude · Posted

      No such thing as regenerative braking on a pure ICE vehicle.     Regenerative braking is the re-capture of energy from electric motors and stores it in the battery pack.  So hybrids, PHEV and EVs have regenerative braking.     What you are seeing is the charging system changing modes is all.  Its likely entering charge mode for some sort of reason is all.  All of the charging modes will be listed below.   As for L10 vs D.  L10 turns off automatic grade braking.  L10 puts you in control of grade downshifts where in D it will automatically do it based on brake pedal position and other factors.  Otherwise L10 and D drive exactly the same aside from that one aspect.    Battery Sulfation Mode The BCM will enter this mode when the interpreted Generator output voltage is less than 13.2 V for 45 minutes. When this condition exists the BCM will enter Charge Mode for 2–3 minutes. The BCM will then determine which mode to enter depending on voltage requirements.   Charge Mode The BCM will enter Charge Mode when ever one of the following conditions are met:   Windshield wipers are ON for more than 3 s. Climate Control Voltage Boost Mode Request is true, as sensed by the HVAC control module via serial data. High speed cooling fan, rear defogger, and HVAC high speed blower operation can cause the BCM to enter the Charge Mode. The estimated battery temperature is less than 0°C (32°F). Battery State of Charge is less than 80%. Vehicle speed is greater than 145 km/h (90 mph) A current sensor malfunction exists. System voltage is determined to be below 12.56 V When any one of these conditions is met, the system will set targeted generator output voltage to a charging voltage between 13.9–15.5 V, depending on the battery state of charge and estimated battery temperature.   Fuel Economy Mode The BCM will enter Fuel Economy Mode when the estimated battery temperature is at least 0°C (32°F) but less than or equal to 80°C (176°F), the calculated battery current is less than 15 A and greater than −8 A, and the battery state-of-charge is greater than or equal to 80%. Its targeted generator output voltage is the open circuit voltage of the battery and can be between 12.5–13.1 V. When fuel economy mode is active, the generator is not charging, only maintaining open circuit battery voltage. The BCM will exit this mode and enter Charge Mode when any of the conditions described above are present.   Headlamp Mode The BCM will enter Headlamp Mode when ever the head lamps are ON (high or low beams). Voltage will be regulated between 13.9–14.5 V.   Start Up Mode When the engine is started the BCM sets a targeted generator output voltage of 14.5 V for 30 s.   Tow/Haul Mode (if applicable) Pressing the Tow/Haul Mode button located on the center stack, the vehicle system voltage is raised and the remote (non-vehicle) battery will be charged. Having the headlamps on will raise the system voltage and if the Tow/Haul button is applied it will not serve any purpose. The voltage is regulated between 13.9-14.5 V.      

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...