DFM shudder/vibration getting worse

matt grz · January 3, 2023

27 minutes ago, Weaverstreet said:

My 2019 LT 5.3 with an 8 speed is experiencing the shudder again and the service writer at Covina Hills Chevrolet told me that this time it's because I had it in 4 wheel auto (It's raining) . The advisor told me that the front and rear axle ratios are not the same and this is the cause when you run it in 4 wheel auto. That sounds very odd to me? GM's brochure states tht you can leave it in 4 wheel auto continuously. I had a video of it surging up a hill and they were not interested in watching it whatsoever. Feels like I'm getting scammed or they are trying to wait until it passes 36K and they can charge me for the repair. This is it's second time it's in for the issue. The first time they held it for a few days saying they couldn't get it to act up before they finally said it was fine after they inspected the pan magnets for metal. It ran fine for a couple of days afterwards and then slowly returned to it's herky-jerky self. Now they want me to miss more work to come and ride around with the technician so he can try to feed me more bs I guess. Now Why would I ever consider another GM product? I miss my 07 now.

I’m going through the same thing. I was called and said they can not recreate the issues, but are going to have a more experienced technician drive it. Hopefully the more experienced technician knows what to look for.

Its very frustrating and I just want it fixed. It’s a shame too because I love the truck, but this issue makes me hate the truck so much that I don’t even want to drive the damn thing.

Transient · January 5, 2023

Tyler,

For some reason I'm having difficulty responding with a quote. Can you please stop playing mental gymnastics. I did not state, nor indicate, the Magnuson Moss Warranty Act gives total protection to the consumer. It does give the consumer protections from negligent producers. As i very clearly stated, GM would need to prove the pulsar device was the cause of the problem. Has such activity been taken? Based on the OP's statements, possibly not. Statements from the OP are going to be one-sided, and should be taken as such. However, that doesn't mean they aren't being fully honest. With that said, the pulsar may not be the cause of the problem, and may also not be used in a manner that would alter the vehicle. Should the warranty be voided for simply plugging in an OBD2 scanner, too? GM is definitely heading that way since they are opposing "right to work on your own vehicle" legislation. In the future I hope you take text at face value and not perform mental gymnastics to manipulate what is said for your miniscule benefit. Trying to tear people down does not lift yourself up.

Edited January 5, 2023 by Transient

GMCustomerService · January 9, 2023

On 1/3/2023 at 5:57 PM, Weaverstreet said:

My 2019 LT 5.3 with an 8 speed is experiencing the shudder again and the service writer at Covina Hills Chevrolet told me that this time it's because I had it in 4 wheel auto (It's raining) . The advisor told me that the front and rear axle ratios are not the same and this is the cause when you run it in 4 wheel auto. That sounds very odd to me? GM's brochure states tht you can leave it in 4 wheel auto continuously. I had a video of it surging up a hill and they were not interested in watching it whatsoever. Feels like I'm getting scammed or they are trying to wait until it passes 36K and they can charge me for the repair. This is it's second time it's in for the issue. The first time they held it for a few days saying they couldn't get it to act up before they finally said it was fine after they inspected the pan magnets for metal. It ran fine for a couple of days afterwards and then slowly returned to it's herky-jerky self. Now they want me to miss more work to come and ride around with the technician so he can try to feed me more bs I guess. Now Why would I ever consider another GM product? I miss my 07 now.

This is certainly not what we like to hear, Weaverstreet. 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 2019 Chevrolet Silverado LT. To do so, please send an email to [email protected] with ATTN: Weaverstreet/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.

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matt grz · February 12, 2023

So after a little mayhem with a GMC dealer I went to a Chevy dealer who found the valve body to be bad. They replaced the valve body and this thing has never ran so good!

thank you gm customer service for helping me through the whole process and for being my go to people to vent to lol! You are very much appreciated!

Brandoneon01 · August 2, 2023

On 2/12/2023 at 11:47 AM, Matt Grz said:

So after a little mayhem with a GMC dealer I went to a Chevy dealer who found the valve body to be bad. They replaced the valve body and this thing has never ran so good!

thank you gm customer service for helping me through the whole process and for being my go to people to vent to lol! You are very much appreciated!

Was it a like you were driving over tiny bumps in the road? And sounds like a slight rumble? I’m getting that with very light throttle around the 35-50 mph range, and low rpm’s just maintaining speed. I have a 2023 gmc Sierra and they’re telling me it’s the DFM and there’s nothing they can do, even though my 2017 GMC Sierra never did this with AFM. Wondering if I need to contact GM before I get rid of this thing and ask about the valve body

matt grz · August 2, 2023

Yeah, I have it at every speed. Little bumps or It almost feels like your spark plugs are bad or something. The valve body replacement seemed to make it better for a little while but it’s back to driving like crap. I took it to about another half dozen dealers and got another half dozen excuses. I’m at the point where I hate this truck and will never buy another GM truck again.

Brandoneon01 · August 2, 2023

6 hours ago, Matt Grz said:

Yeah, I have it at every speed. Little bumps or It almost feels like your spark plugs are bad or something. The valve body replacement seemed to make it better for a little while but it’s back to driving like crap. I took it to about another half dozen dealers and got another half dozen excuses. I’m at the point where I hate this truck and will never buy another GM truck again.

I don’t blame you at all, we spend too much money on these trucks to drive us nuts and not genuinely enjoy them, I started a claim with GM about it, not sure that’s even worth it after hearing your experience.

matt grz · August 3, 2023

Yeah, it’s a total bummer. Makes me not even want to drive the stupid thing. I wish I would have went with one of those 3.0 diesels.

I hope the claim works out for you though man. Keep me posted. I’m curious how your GM journey is going to be lol.

matt grz · November 26, 2023

On 8/2/2023 at 12:48 PM, Brandoneon01 said:

I don’t blame you at all, we spend too much money on these trucks to drive us nuts and not genuinely enjoy them, I started a claim with GM about it, not sure that’s even worth it after hearing your experience.

Did you ever figure out your vibration issue? It took me about a dozen dealers and several GM customer service reps, I don’t want to jinx anything so knock on wood, but it seems like a new torque converter resolved my vibration issues. Just some friendly information. Thanks.

Gangly · November 27, 2023

There is a known issue on some models with transmission mount failures that can create vibration issues. Check your transmission mounts.

matt grz · March 12, 2024

Vibration is back lmao wtf! I’m not really sure how to check the transmission mounts. I see the tsb pip 5705, but I’m not really sure what I’m looking at. Might have to go back to the dealer. Sick of paying diagnostic fees though! Any advice?

lennybg · March 13, 2024

Having a device plugged into your ODB port does not void the warranty.. If that was the case there would be lawsuits out the ying yang towards insurance companies that have devices that plug into the obd port to monitor driving habits for insurance coverages.

Gangly · March 14, 2024

15 hours ago, lennybg said:

Having a device plugged into your ODB port does not void the warranty.. If that was the case there would be lawsuits out the ying yang towards insurance companies that have devices that plug into the obd port to monitor driving habits for insurance coverages.

Monitoring driving habits (GPS Tracker) is far different than altering vehicle driving parameters. Voiding of a warranty all depends on what the device plugged into your OBD port does, and yes, having devices plugged into your OBD port WILL void certain aspects of your warranty.

matt grz · March 14, 2024

Damn guys, f*ck that pulsar and OBD bullsh*t. Everyone has all of their own opinions on the subject and none of them are right. I just want this damn truck to stop running like piece of sh*t and I am doing everything I can to pin point the problem because the majority of these GM mechanics out there aren’t qualified to pull the hood release latch let alone troubleshoot something.