Jump to content

AFM vibration in V4 mode

SOL24/7
 Share

Recommended Posts

Sierra Dan Senior Enthusiast

Sierra Dan

Posted
Posted
16 hours ago, dspar00a said:

Mine are in the floorboard and foot pedal mostly. But, not at 1500 or higher. For me, it's 12-1300 and lower. 

 

Do you know if there is a fix for this? It has made me consider trading and going to another brand. I love this truck and have always been a GM person. But, I don't want to go get into another truck and it be the same story. Nor, do I really want to have to go get back into another loan if this problem can be fixed. 

There is a thread on it somewhere...… no fix as of yet.

Conspiracy theories include harmonic exhaust vibration, torque converter problems and a couple of other guesses.

  • 7 months later...
  • Replies 37
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

Thomcat
Thomcat

.02   AFM problems in earlier engines resulted in oil ring clogging and oil fouling of plugs usually presenting after 50K miles and effects noted in both V4 and V8 modes. Engine modifications subseq

High Country 6.2L/8
High Country 6.2L/8

Did you try Amsoil ATF? I did swap a year ago through warranty which dealer paid for and no issues since. That Mobil fix is garbage that fluid doesn't hold a candle to Amsoil and the proof is in the p

High Country 6.2L/8
High Country 6.2L/8

Did a AFM delete with Range and the clunking seems to have left for the most part. Dealer is going to do a relearn only a bandaid fix in my opinion. GM needs a software update 

Trnr1995 Enthusiast

Trnr1995

Posted
Posted
On 1/16/2019 at 1:12 PM, dspar00a said:

I have had tons of issues with my Sierra since I have purchased it. I have had vibrations/shift issues from day one and had my truck in the shop 6 times now to always be told what I am experiencing is normal. My issue always comes from switching from V4 to V8 and it is either a slam like shifting up or down into gear or if in V4 and at a constant low speed. The truck acts as if it has shifted up to 6th gear at 35-40mph and vibrates as if it's about to die. My RPM's drop usually below 1,000 and it's just too high of a gear for that range. 

 

My frustration that my dealer just refuses to act like there is anything abnormal with it. It's bad when my passengers ask if my truck is fixing to break down. I took so outside clients from my work out to lunch one day and they were all worried we were going to have mechanical issues. I just don't think that's normal and if it is, why would GM want this for their $40,000+ vehicles? My brother has the same truck as I but a 15' and his is 100% more smooth than mine. The only fix I have found is driving in M5. It's like a whole different truck. 

Any fix yet? Just got truck back from getting new lifters, cam etc. Truck ran great before collapsed lifter. Now new parts and it vibrates and shudders between 45 and 60.

High Country 6.2L/8 Enthusiast

High Country 6.2L/8

Posted
Posted
On 10/11/2016 at 8:14 AM, silveradosid said:

i also have the v4 vibration and it doesnt matter what speed i am doing, if it goes into v4 mode the vibration starts. what sucks is this truck ran perfectly smooth until it 50k kilometers. then the vibration started and now at 60k it is getting worst and of course the stealership says they dont notice anything different

Did you get the issue fixed? Myself have a 17 High Country 6.2L I went to dealership and they did a triple flush and I dumped the factory shit with Amsoil ATF and dumped all other fluids and switched to Amsoil. I've never had any issues but it only has 31,000 kms.

silveradosid Senior Enthusiast

silveradosid

Posted
Posted

no never did resolve the vibration, even after putting a new exhaust system on. i bought a programmer and turned the afm off . there is a slight change in fuel mileage but no more vibration

  • 1 month later...
JFREED Enthusiast

JFREED

Posted
Posted

I have been having a similar issue, seems to be after v4 to v8 and under 2000rpms with the greatest noise being at 1100-1300. The rpms fluctuate up and down 200 with steady pedal. I’m over the “warranty” and have been told numerous possibilities as to the cause. It sounds like a chatter, with vibration, and after reading some of the forums I have been driving in M5 without the noise. Can I continue driving it like that? Is it ok to do at interstate speeds? I love the truck otherwise but now wish I had kept my Toyota. 

  • 2 weeks later...
High Country 6.2L/8 Enthusiast

High Country 6.2L/8

Posted
Posted
On 11/4/2019 at 10:55 PM, JFREED said:

I have been having a similar issue, seems to be after v4 to v8 and under 2000rpms with the greatest noise being at 1100-1300. The rpms fluctuate up and down 200 with steady pedal. I’m over the “warranty” and have been told numerous possibilities as to the cause. It sounds like a chatter, with vibration, and after reading some of the forums I have been driving in M5 without the noise. Can I continue driving it like that? Is it ok to do at interstate speeds? I love the truck otherwise but now wish I had kept my Toyota. 

Did you try Amsoil ATF? I did swap a year ago through warranty which dealer paid for and no issues since. That Mobil fix is garbage that fluid doesn't hold a candle to Amsoil and the proof is in the pudding with my truck 

  • Like 1
High Country 6.2L/8 Enthusiast

High Country 6.2L/8

Posted
Posted
8 hours ago, JFREED said:

No I haven’t. I am thinking it’s the AFM system. 

Did a AFM delete with Range and the clunking seems to have left for the most part. Dealer is going to do a relearn only a bandaid fix in my opinion. GM needs a software update 

  • Like 1
TXGREEK Senior Enthusiast

TXGREEK

Posted
Posted
Did you try Amsoil ATF? I did swap a year ago through warranty which dealer paid for and no issues since. That Mobil fix is garbage that fluid doesn't hold a candle to Amsoil and the proof is in the pudding with my truck 


You’re absolutely correct, it’s made a big difference for me as well.


Sent from Above
  • 1 year later...
Marshall_13 Enthusiast

Marshall_13

Posted
Posted
On 5/10/2017 at 11:03 AM, 2015MDNT said:

I have the same issue, and mine started at 44K miles. I noticed it first when I have the transmission in drive and the truck is stopped, like at a light. If I shift to neutral the shudder or vibration goes away. I just got back from a 4K road trip, and I noticed at cruise of 80mph that in V4 mode the shudder was there. As soon as V8 kicked in, the shudder or vibration could not be felt. I believe that the extra 4 firing cylinders are masking the vibration. I am at the dealership right now expecting to pay $118 for a diagnostic that says they found nothing.

 

One caveat is I hit some heavy bumps on a short off-road experience. I noticed the vibration after that event. It may not be related, but think it's worth noting.

Hello, was the dealer able to resolve this issue?  I’m having the same issue on my 2018 5.3 at around 80 mph. Thanks! 

  • 3 weeks later...
steveos3312 New Member

steveos3312

Posted
Posted
On 11/5/2019 at 2:55 AM, JFREED said:

I have been having a similar issue, seems to be after v4 to v8 and under 2000rpms with the greatest noise being at 1100-1300. The rpms fluctuate up and down 200 with steady pedal. I’m over the “warranty” and have been told numerous possibilities as to the cause. It sounds like a chatter, with vibration, and after reading some of the forums I have been driving in M5 without the noise. Can I continue driving it like that? Is it ok to do at interstate speeds? I love the truck otherwise but now wish I had kept my Toyota. 

Are you still having these issues? Did you find a solution or explanation? Still riding interstate in M5?

JFREED Enthusiast

JFREED

Posted
Posted

It wound up being my torque converter was going out I got my transmission rebuilt no more issues. Also I was having an issue with my mileage and weird shifting that I thought was related to the tranny, turns out that was the MAF sensor needing to be cleaned. That was easy to do just buy the cleaner made for it. 

flyingfool Senior Enthusiast

flyingfool

Posted
Posted (edited)

if its the TCC in the converter causing the vibe, i suggest having a tuner ad more line pressure to the clutch, and correct input/output rpm slip table, then only engage the tcc at 5-6th gears, stock tune has the tcc locking in all gears, this is wearing out the tcc clutch

dont forget to do a Fast Trans re-learn after its set up..

Edited by flyingfool
  • 3 months later...
Darthmalo Enthusiast

Darthmalo

Posted
Posted (edited)

Hello Any solution to this issue?   My truck have this vibration noise from V4 mode to V8.  Going to the dealer this week for service and check this.

Edited by Darthmalo
  • 4 months later...
R3SS0X New Member

R3SS0X

Posted
Posted
On 3/29/2021 at 10:30 AM, Darthmalo said:

Hello Any solution to this issue?   My truck have this vibration noise from V4 mode to V8.  Going to the dealer this week for service and check this.

Any luck? Mind started this today. 

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

    • Tyler Gibbs
      Travel Trailer 2024 2500 HD 6.6 Gas Engine ?

      By Tyler Gibbs · Posted

      The curb weight on a 1 ton crew cab long bed is around 7k lbs.  Now, I don't know where you went to school but 9k is not more than 2x 7k lbs. More than 2x 7k lbs would be 14k+.   With that said, obviously yes you're going to feel a 9k lb trailer when slowing down.  I already said, when accelerating.  When changing lanes?  No.  But if you look at the context of what was quoted, the original person said, "after a mile or two..." which means that would be after the accelerating portion and you're driving a generally steady pace.  Please do learn to read and comprehend.
    • sFrank
      2026 Silverado Range AFM DFM ECU loaction

      By sFrank · Posted

      So I purchased the Range unit for my 2026 and I am seeing different locations suggested for the ECM . Can anyone confirm wither under hood, left side or right side or behind the wheelwell?
    • No F-bdy Bs
      Dave's Auto (custom engine builder) tear down of L8T

      By No F-bdy Bs · Posted

      Like I've said before. Di and Carbon buildup is not that big of a concern. Engine had minimal buildup, and that engine was obviously not super well maintained. Do regular oil changes, and you're gtg as long as the rest of the truck lasts. Also, the High Pressure FP that people ****** about, but can't tell you why.  Now, I wish they'd trash the variable oil pump. No real world issues with them, but I'll gladly eat whatever miniscule MPG it's saving me in favor of more oil at all RPMs.    Curious to see his assessment of the 7.3 compared to the 6.6. I expect he'll praise the port inj, but from a structural standpoint, the 6.6 is as robust as any engine out there.    Not to take away from the 7.3. I feel it's equally as good as the 6.6.     As to heat on the rear cyls, I'd have to see numerous examples before I'd say it's an issue. Especially not knowing the history of that engine. For all is known, they could have blown a rad hose, and ran it hot, and the 2 rear cyls may be the first to get hot in a low coolant situation, but not be an issue aside from that. 
    • Donstar
      Navigating senior years.

      By Donstar · Posted

      "Life is getting back to normal."    I'm driving again and all new joints are operating as expected for this stage of recovery.   My most recent joint replacement still requires a lot of attention but experience has taught me that time will quiet the remaining pain.  I joked with my surgeon that another joint replacement would take my mind off my most recent surgery and he responded by saying the next will be a hip!  There are no plans for another surgery but, unlike me, I don't think he was joking!  I certainly wouldn't refuse further replacement  if required but hope to spend time out of the "post-op"  period.  I can't stress enough that if you have been recommended for total hip, knee or shoulder replacement that you welcome the offer.  Post-op "recovery" may sound daunting and painful, however, this is far better than the insidious erosion of mobility you are currently experiencing.  Imagine what it would feel like to wake up most mornings feeling better and more mobile than you did the previous day!  Prior to my first surgery in June 2025, even getting out of bed was becoming a formidable task.  Since the day after my first surgery, I get out of bed everyday easily and unassisted.  Making the switch to feeling a little better each day rather than a little worse, is hugely motivating!
    • Coastie05
      ‘25 Silverado purchase- back to dealership for bumper/radio issue

      By Coastie05 · Posted

      Hope it all works out for you. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...