Jump to content

Recommended Posts

Posted
On 10/2/2021 at 1:25 PM, Sam Fargo said:

So a further update after a month in the shop they replaced lifter guides and fuel rails and gave me truck back and said it was cylinder 2 lifter bleeding out that was causing the misfire which felt like people a stutter at low rpms. So since this shaking started they replaced camshaft position sensor and that wasn’t it. Now they have replaced lifters cause cylinder 2 had a bleeding lifter and that wasn’t the problem either. Truck still shakes and stutters. Does any one see a problem with this I’ve brought truck in twice with no CEL and they found big problems each time but still haven’t fixed the problem the truck was brought in for. This seems unbelievable. The truck has only 1200 miles now and its two months old and now is going in shop for the third time to fix same issue that hasn’t been addressed but they keep finding bigger problems each time they look into it. I’m at disbelief did they just rebuild the top end for nothing. Furthermore on paperwork they stated they test drove vehicle after repair and it was fine. But I looked at the Chevrolet app and it says no miles were driven on my truck after the date they said they repaired. This thing is becoming highly suspicious I’m not sure the dealer is doing anything but giving back truck after holding it for a month

Did you ever figure out this issue? I’m having the same thing going on with my 2023 GMC Sierra 

  • 6 months later...
Posted

Hello all 

Mine is a 2020 silverado custom 2.7L  turbo and it does the same but what I've notice watching the rpm it does it as I accelerator a small amount and it shifts back and forth between gears  I think it has something to do with that I checked all my u joints they're all good and all mounts are good only does it at low speeds and a little bit of throttle just when your trying to keep at a speed around 40-60km/h

Posted
On 2/22/2024 at 4:54 PM, Hadrian said:

Hello all 

Mine is a 2020 silverado custom 2.7L  turbo and it does the same but what I've notice watching the rpm it does it as I accelerator a small amount and it shifts back and forth between gears  I think it has something to do with that I checked all my u joints they're all good and all mounts are good only does it at low speeds and a little bit of throttle just when your trying to keep at a speed around 40-60km/h

This is certainly not what we like to hear, Hadrian.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2020 Chevrolet Silverado having a vibration at lower speeds. To do so, please send an email to [email protected] with ATTN: Hadrian/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s Privacy Policy, please visit https://www.gm.com/privacy-statement.html. The information you provide may be monitored and recorded and is subject to the GM Privacy Statement.
 
Privacy Statement | General Motors
Your privacy is important to General Motors. This Privacy Statement addresses the personal information GM collects and how GM handles that personal information.
www.gm.com
 

  • 1 year later...
Posted

Hello everyone, I have a 2020 Sierra 5.3 Rwd. Experiencing similar issues as described. Has anyone found a fix?

Watched the live data and saw multiple misfires among multiple cylinders, changed the spark plugs and no luck. 

 

Posted
5 hours ago, Mike duval said:

Hello everyone, I have a 2020 Sierra 5.3 Rwd. Experiencing similar issues as described. Has anyone found a fix?

Watched the live data and saw multiple misfires among multiple cylinders, changed the spark plugs and no luck. 

 

We would like to get you into the dealership for assistance, Mike. We can be reached via email at [email protected], and ask that you reach out there with your VIN so we can take a look at your dealership's availability. By sending us a message, you consent to the information you provide being monitored and recorded by GM or those acting on GM’s behalf, subject to the GM Privacy Statement: https://www.gm.com/privacy-statement.

  • 4 months later...
Posted

Just wanted to update the forum. After chasing the misfire for so long, I gave up and took it to Chevy and had them run a diag. The tech came back with a bad torque converter. 

Ordered ($621) and had it replaced with fresh trans fluid, its driving good now. Will update after a few thousand miles.

Interesting enough no codes for judder/shudder/slippage. 

 

I'm assuming the ecu pulls fuel when it senses the trans starting to slip? FYI this truck only has 50k miles.

  • 1 month later...
Posted

I have a potential solution to this issue. 2024, work truck, 5.3, crew cab. 10 speed. In the mornings, when I pull off, I can hear what sounds like my rear brake calipers sticking… But the way the noise sounds, it sounds like the rotors are warped. I’m 99% sure that the rear rotors are warped and that’s causing the issues with highway vibration. I’m having it checked this Friday, will keep you guys posted. Someone else posted the same issue in this forum a few months ago. We never heard back from him. I’ve noticed that the vibration will smooth out after a while, long after the brakes are applied… Which is another thing that clues me into the possibility of rotor warpage being the problem. My truck has 10,700 miles on it, and it’s done this since new… Different tires, different wheels, comes from the same place after rotation. It’s definitely coming from the rear. Even though I can feel it in the steering wheel, it feels more so like it’s coming from the back of my seat bottom.

  • 3 months later...
Posted

did you happen to figure out what the issue was? i have a 2023 silverado 1500. z71 RST package. 23k miles. when my rpm's hit about 1k especially at low speeds i feel the shake/vibration and it seems to get worse. if you figured it out please let me know. thanks

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

    • Did have to make 1 modification because of the WeatherTech rear mud flaps and that was needing 3 longer screws than what came with the install package. 😄
    • Picked up the liners yesterday. Installed passenger side WITHOUT any modifications. All mounting holes lined up perfectly. Rain is interfering today with drivers side. Very Happy! Will add pics when finished
    • As a matter of amusement I’ll leave this conversation with this. Do you beat the government average fuel estimate? Statistics are a guide to me. Not a rule. Someone once said I have to have the last word. If true and possible may be. I’ll blame that on working in a family business.
    • That is a fair point, and I agree that trying to log “everything in the truck” would be the wrong direction.   There are a lot of modules and a lot of traffic. If the product became a full-truck datalogger, the amount of data would get huge very quickly, and most owners would never use it.   I think the first useful version would need to be narrow: - powertrain-side event evidence - selected high-value parameters - communication / voltage / reset events - pre/post event window - short report first, raw log only as backup   One distinction I should make is between active OBD/PID polling and passive bus capture. If you are polling PIDs through OBD, then yes: the more parameters you request, the lower the effective sample rate becomes, and you are adding diagnostic traffic to a vehicle that is already busy running itself. With passive CAN capture, the recorder is not asking all the modules for data. It is listening to traffic that is already on the bus. So it does not consume vehicle bus bandwidth in the same way that a scan tool polling hundreds of PIDs would. But your point still applies in a different way.   Even if passive capture does not add bus traffic, the recorder still has limits: - processing rate - storage rate - timestamp accuracy - decoder workload - event filtering - report size - user attention span   So the answer cannot be “log everything and let the user figure it out.” The product would need to store enough raw evidence to be useful, but only decode, graph, and present the important parts around the event.   A practical report should probably show: - what triggered the capture - how much pre/post data was preserved - which selected parameters changed - how those values compared to baseline - whether the same pattern happened before - whether any voltage, reset, bus-off, lost-message, or communication fault occurred - selected graphs around the event - raw data only as supporting evidence   So I agree with you. More data is not automatically better. The real product is the reduction from raw data into a useful event report.
    • That makes sense, and I agree with most of that.   I think the product would need both: 1. a default powertrain template, so it is useful out of the box; 2. user-selected priority parameters, so the owner or shop can choose what they want to see first.   Different users are going to care about different things. One owner may care about oil pressure and voltage. Another may care about misfire trend, AFM/DFM behavior, or U-codes. A shop may want communication events and repeatability first. Your baseline point is probably the most important one. Raw data is not very useful unless the report can show what normal looked like for that vehicle under similar conditions.   The way I would think about it is: - start with a basic known-good baseline - learn normal behavior for that specific vehicle over time - allow the event to be overlaid against baseline - show whether the event was a one-time spike or a repeatable pattern - provide a simple severity level, but with clear limits on what that severity means   For example, early severity could be something like: - Info: event captured, no obvious abnormal pattern - Watch: value moved outside baseline, but not repeated - Warning: repeatable abnormal pattern under similar conditions - Critical: communication loss, voltage drop, bus-off, reset, or severe repeated event   I would not want the first version to say “replace this part.” That would be overclaiming unless there is repair-confirmed data behind it. It would be more honest to say “this pattern deserves inspection.”   On the OBD port question, I think OBD absolutely has a role. OBD is probably the right place for: - DTCs - freeze frame - VIN - calibration information - normal scan-tool parameters - Mode 6 / enhanced diagnostic data if available The reason I am still looking at an ECM-side recorder is that the failure may happen before anyone connects a scan tool. If the owner plugs in a scanner after the event, the pre-event evidence may already be gone unless the ECU happened to save it. So I do not see this as “OBD versus ECM-side.” I see it more like: - ECM-side recorder: always armed, rolling buffer, event evidence - OBD/DLC companion: DTCs, freeze frame, VIN, calibration, normal scan data - phone/cloud: status, notes, upload, report generation, notifications   I agree that phone connection and push notifications would be useful. I just would not want the phone or cloud connection to be required for capture. The recorder should save the event locally even if the phone is not connected. The phone should help with event marking, download, notes, upload, alerts, and report viewing.   For a default GM V8 event report, would this list make sense? - RPM - calculated load / MAP - throttle position - vehicle speed - gear / torque converter state if available - coolant temperature - oil pressure - oil temperature if available - battery voltage - commanded AFM/DFM state if available - actual AFM/DFM state if available - misfire counters / roughness by cylinder if available - fuel trims - relevant U-codes / communication events - bus-off / lost periodic message / module reset / voltage drop events Which of those would you remove, and what would you add?
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...