Jump to content

Recommended Posts

Posted

Mine had vibrations when I bought it... drove it home 550 miles.  Next day drove down to my local tire shop and put brand new Michelin LTX AT2s on and its been butter every since.  Most good tire shops will give you a decent return on nearly new tires so its a win win to me.  Spend 70-80k on a truck and complain about tires, or spend 70-80k and replace the crap stockers and go on down the road.

  • 2 weeks later...
Posted

Just bought 2020 3500 DRW diesel to pull my RV. I had "shimy/shake" vibration from day one. Came with Michelin tires. Turned out the truck needed two tires rebalanced (one big time), tires needed inflated to specs, and front end alignment. Took two trips to the dealer. Came off the delivery truck like that. You'd think for $70K you might get some QA at the GM factory. Currently have door ajar light on, driver cannot roll windows down, interior dome lights don't come on when door opened. Window lock not working. Going to have dealer also look at this Friday. No doubt a window motor, harness issue, body modulator or something. If Toyota made these type of heavy trucks, I would not think twice about buying one. GM is not too big to fail as far as I'm concerned. Keep it up GM and go out of business. Last one to leave in Flint Mich. be sure to turn the lights out.

Posted

This is on Google Map when you look up the old closed down Mitsubishi plant in Normal Illinois. The last guys to leave apparently had access to a forklift and some empty parts racks and of course a sense of humor. Maybe the last ones out at GM will do something like this Haha

We can all buy a Rivian Electric truck maybe? 

 

Post image

 

Rivian quietly brings former Mitsubishi plant back to life

 

  • 6 months later...
Posted

I have a 2020 Chevy HD. LTZ with the magna steering option. Bought new in Sept. 2019. Been in the dealer now 6 times for steering wheel shake at hwy. speeds and rattle like vibration in the steering wheel. Dealer has done 2 alignments. 2 software upgrades multiple force balance and still have not corrected this issue. Going back this week. GM TAC is involved. They can’t repair it. Drove a new High country last time with the service manager and it had the same problem. So it’s still an issue. 

Posted
6 minutes ago, Patrick McClain said:

After last repair seems to be doing it at lower speeds now. WTH!! Anyone else seeing this? 
lots of vibration in the steering wheel on curves and bumps. 

Last week I had a pretty bad vibration on my 2500 AT4 from about 67mph to 80. They road force balanced them and now the truck is happy. Hopefully they get yours fixed, but if not, it may be time to start talking with someone about a potential buy back.

Posted

If it is at low speeds it is more a function of the steering software update and dealer not following the procedure.  A lot of them have not been clearing the offsets in software history after the reflash.  

 

#iworkforGM 

Posted

After the last reflash it’s more noticeable at 40 mph and up. It’s weird. GM is basically saying it’s road conditions now. Funny that my 2016 HD didn’t react this way to the same road conditions. I must say the Dealer is “trying’” to fix it though. 

  • 4 weeks later...
Posted

Purchased a 2020 GMC 2.7L sierra two months ago and I noticed on highway speed 70+ mph the truck will shake.  Took it to the dealer where they performed a road force balance on the tires and told me it was fixed.  Just drove it this morning on the highway to work and I still feel it. 

 

Posted

It could be tires. My wife’s car is tire sensitive. The original tires got loud and vibrating at 30K miles. I replaced and at 20K they started doing the same. Most people would have done an alignment. With the ties being rotated every 4K miles with oil changes, there was no uneven wear. Discount tire agreed and gave me a pro rated change. The next set went almost 60K with no problem. I can hear the new set starting to sing. That was all over ten years of ownership. I do notice with all my vehicles road surfaces can effect a vehicles drivability. Especially if heavy trucks frequent the road. There one road that appears smooth. With heavy trucks frequently using it. There’s tiny ripples all along it. It’s noisy and vibrates. I could make a person think there’s a problem with their vehicle. You can see the imperfections in the rain. It not uncommon for people to pull over and check out their vehicle.


Sent from my iPhone using Tapatalk

  • Like 1
Posted
22 hours ago, KARNUT said:

It could be tires. My wife’s car is tire sensitive. The original tires got loud and vibrating at 30K miles. I replaced and at 20K they started doing the same. Most people would have done an alignment. With the ties being rotated every 4K miles with oil changes, there was no uneven wear. Discount tire agreed and gave me a pro rated change. The next set went almost 60K with no problem. I can hear the new set starting to sing. That was all over ten years of ownership. I do notice with all my vehicles road surfaces can effect a vehicles drivability. Especially if heavy trucks frequent the road. There one road that appears smooth. With heavy trucks frequently using it. There’s tiny ripples all along it. It’s noisy and vibrates. I could make a person think there’s a problem with their vehicle. You can see the imperfections in the rain. It not uncommon for people to pull over and check out their vehicle.


Sent from my iPhone using Tapatalk

Agreed. Many times, you can see the ripples on the highway. Just a slight variation in color/shadow on the road is the ripples. I’ve found that concrete highways are the smoothest, but are more expensive and slower to build. Most asphalt highways with a lot of use are repaved every few years. Interstates that are asphalt don’t last long at all.

  • Like 1
Posted
On 9/1/2020 at 6:30 PM, Patrick McClain said:

I must say the Dealer is “trying’” to fix it though. 

Have them run a picoscope on it to confirm the source of the issue.  Sounds like they're just taking stabs in the dark on the usual suspects.

Posted

They have ran several picoscopes to my understanding. They (GM) actually wrote a new calibration For the vehicle that did seem to help the shake problem. I’m thinking this Truck has a BCM issue. The other morning I came out to a dead vehicle. Had to jump it off. Drove it to the dealer. It had multiple codes in it. Steering shake came back on th trip to the dealer. Then after the codes were cleared it seemed to be fine. They replaced the battery per my request so at least something would be done. Weird thing too is that all of my engine hours got cleared out. Trip reset to the vehicle miles. Strange!!  Anyway I’m done with it. Going to replace it. 

Posted (edited)

I think alot of vibrations are  being blamed on the trucks, when in actuallity it's the paved road surface.  we have a fairly long wheelbase and depending on the paver wheel base used to smooth the roads, we might be syncing up with the  sin wave created by the paver or long tracker trailers that deformed the surface..

 

i prrooved my theory this weekend by visiting a local dry lake in the area El MIrage California, completly flat , no woops or undulations.  my vibration occurs at 78mph and carries on towards 100+mph on paved highways..  on the dry lake  i held the same speed range til i hit engine kill speed 105mph and absolutly ZERO vibrations!!!

 

its not the wheels or anything else

Edited by flyingfool
  • Like 1
Posted
59 minutes ago, Patrick McClain said:

They have ran several picoscopes to my understanding. They (GM) actually wrote a new calibration For the vehicle that did seem to help the shake problem. I’m thinking this Truck has a BCM issue. The other morning I came out to a dead vehicle. Had to jump it off. Drove it to the dealer. It had multiple codes in it. Steering shake came back on th trip to the dealer. Then after the codes were cleared it seemed to be fine. They replaced the battery per my request so at least something would be done. Weird thing too is that all of my engine hours got cleared out. Trip reset to the vehicle miles. Strange!!  Anyway I’m done with it. Going to replace it. 

I'd ask to see them.  Picoscope should hopefully be fairly clear as to the source of the vibrations or classification of it. (Is it aligned with tires, prop shaft or engine rpm and which order). Its rarely used and voided so they may not be too familiar with it.

 

Sounds like electrical or BCM related but yes after a battery dies or truck loses power it will have quite a few codes and may ride differently for a while as it needs to relearn some of the drive characteristics.  I'd expect most of the codes to be "communication lost" codes with the BCM since many systems connect to BCM.

 

Engine hour cleared out is a common issue when power is lost as that's stored in the instrument cluster control module and doesn't always persist loss of power.

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

  • Latest Articles

  • Posts

    • hello I recently bought a 2012 gmc 1500 with a 5.3 and have a AFM disabler on it I'm interested in doing a cam but I'm worried if I remove the AFM system I will fail smog does anyone have info if they are able to detect that or a work around to it (not talking about hot smogging) please let me know thank you  
    • Update. I started chasing down my symptoms. Started first with pulling valve covers and looked at everything. Everything looked good and couldn't hear or feel anything different. Then a compression test. 240 psi or really close on each cylinder. I was worried I was a tooth off of timing. Not bad for an engine with 173,000. Granted I did put new heads on. I sprayed water around the injector area to see if I could hear a change. Nothing. I hooked up my new hp tuner which I should have done in the first place but I don't really know what I'm looking at just yet but am learning. I noticed the fuel trims were way off so that told me I have to have either a bad injector or exhaust leak. New injectors, so I did the shop vac on blower and in the tail pipe. Sprayed soapy water and found the exhaust flange on the drivers side was leaking. I didn't think it would be that considereding I pulled the heads and left the manifolds attached. I did have the transmission replaced not long ago. They must have not seated them properly but I guess I didn't notice. I put in new gaskets on both sides. Which by the way isn't a bad job but I had a hard time getting them to seal right. Took two attempts. Reset the fuel trims and the ticking is gone, engine runs smooth and acceleration has improved. Got to feel the real difference with that stage 1 cam. It's not that big of a difference but it does add a little more. It feels like how the truck should have been from the factory.
    • 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. 
    • 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.  
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...