issue 2014 rough engine idle

WhiteLTZ14 · March 1, 2014

Got my truck back too.

Honestly, feels the exact same when sitting at idle. The motor isn't idling rough, they checked for stored misfire codes, so I guess everything is fine.

But they did the bulletin re-centering the trans and motor mounts and shimming the motor mount. Feels exactly the same though.

Well just got home after a long drive and the truck doesn't feel as it did before but the somewhat rough idle is still there but its not as bad as it was. Before i could literally see my hands vibrate along with the truck... when i had my 07 tahoe it had the same rough idle feeling to it but it went away after 10k miles on it... my 09 tahoe and 09 silverado were very smooth though... oh well hope it goes away soon after it gets "broken in"

fondupot · March 4, 2014

Mine feels exactly the same. I'm starting to think they didn't do anything to the truck. Just had it for a day and said they did.....

Annoyed.

WhiteLTZ14 · March 4, 2014

Mine feels exactly the same. I'm starting to think they didn't do anything to the truck. Just had it for a day and said they did.....

Annoyed.

I've been driving the truck for a few days now and it actually is alot better now... dont feel the rough idle anymore. Maybe take it to another dealer and see what they say.

ken0072603 · March 10, 2014

Just dropped my truck at the dealer. There is a bulletin on this vibration issue. I saw some of the paperwork and it said something about re-centering the engine/transmission on the mounts and shim the motor 3mm. So they're gonna work on it. I'll report back after. Sent from my iPhone.

I myself dropped the truck off Friday for the same issue. I did the cup of water test just like the other owner. My dealer said nothing is wrong with the engine. He acknowledged the bulletin for the V-8, but since I have the V-6, there is no fix. He said more owners of the V-6 would need to complain to get a fix. Any ideas?

fondupot · March 10, 2014

Yea, my truck is still acting the same. Not sure about the V6 issue. But the motors are all pretty similar apart from 2 less cylinders on a V6. So my guess is something internally is causing excess vibrations....not exactly good for longevity.

I have to go in for an oil change soon, I'm wondering if it will change as the motor breaks in more. I currently have about 5300 miles on the truck.

tenpins77 · March 13, 2014

Any links or updates to this bulletin? Same issue on my 14 .

clearstreamservices · March 15, 2014

I had same rough idling issue, in drive, foot on brake. I took delivery on 2/13/14, noticed idle around 480-490 and rough, if touched gas pedal just a little, vibration went away. After reading about case on this forum, I asked dealer to perform 3mm shim on 2/19/14 , helped but still felt like a misfire. I was busy with work and did not have another day to be without my truck. After a few weeks and 1,200 miles, seems like it has corrected itself. If anyone has any insight, please share...computer corrected the problem itself?

beetle · March 15, 2014

This is just a longshot theory....the gas may have degraded since installed at the factory, look at the build date on the door sticker, it could have been in there for quite a while. Mine had a slight limp too but cleared after a few tanks.

clearstreamservices · March 17, 2014

Very well could have been, had a november build date, didn't purchase till 2/13/14. I was worried at first, turning out to really like my truck!

fondupot · March 17, 2014

I dont think there area any issues with the engines misfiring. Its more of a harmonic balance issue with the way the motor is mounted to the frame. My truck performs great and gets terrific mileage. if it was misfiring, it would be stumbling and getting crappy mileage and throwing engine codes. It's not doing any of those.

This is purely a balance issue and will probably require some finesse on to get it worked out.

I'm heading back into the dealer soon to have my oil changed and have them look at this issue again.

fondupot · March 21, 2014

Dropped my truck off again on Wednesday. I'm driving a loaner sierra to compare and this truck does NOT vibrate at all. It's very smooth. It's a crew cab, SLE with standard bed. IT has 18" wheels and its a regular 4x4, and has 3.08 gears. I have to say it rides a little nicer than my truck with the 20's and Z71 package, not to mention my truck has a shorter wheelbase. But my truck with the 3.42 gears gets up and goes way better. But that's to be expected.

Anyways, I sat in the loaner with my service guy and he agreed. This loaner truck does not vibrate.

So I called today to see how it was going and they said they almost have the vibrations eliminated from my truck. He assured me that the motor is running fine its not throwing any codes, misfiring, or running rough at any capacity, its just an issue of harmonic balancing with the engine/trans mounts to the frame. He said they consulted the GM Engineering department that handles Bulletins and what not and they have been working with them towards a resolution. When I talked to him today he said they had one more thing to do get rid of the vibrations and they were waiting to hear back from GM.

Overall I am pleased with the level of service I am receiving from my dealership. I feel like they are 100% on my side and agree the truck should not vibrate on idle as it does, they are working to make sure the truck is up to spec and that I am left with a smooth idling truck.

I'll post up again when I get the truck back. Hopefully, with no more idle vibrations.

-Out

TonesInGMC · March 21, 2014

Mine doesn't vibrate. Not much anyway but I can here a bit of tick. Is that normal for you other guys? I've got a 5.3

Sent from my Nexus 4 using Tapatalk

Dnt · March 22, 2014

Mine doesn't vibrate. Not much anyway but I can here a bit of tick. Is that normal for you other guys? I've got a 5.3 Sent from my Nexus 4 using Tapatalk

I think all the direct injection engines have a TICK. (Note: "GM has these on a ticking timer and programmed to blow up at 100,001 miles) No seriously the direct injection pump and injectors are VERY noisy they made a lot of sound insulation efforts at the engine but it cannot be completely eliminated. Without the sound covers it would be unbearable. I would not purchase mine after hearing it idle until I started about 1/2 dozen 5.3's on the lot they all had the TICK noise, some were louder than others I would say that mine is around the middle.

On the main subject here of the engine vibration I am going to do that cup of water test on mine today. I find it fascinating that a 3mm shim could actually make a difference. i suspect that there may be some other issue along with the shim that is causing the vibration, maybe a fastener torque problem or frame mount misalignment on certain monday and friday build trucks....... What is your build date for your truck fondupot?

fondupot · March 22, 2014

Got my truck back yesterday afternoon. They recentered everything again and it seems to be better. Before the vibrations would almost surge. They would hit hard, then subside. Now there is a constant slight vibe that lets you know the truck is on. Not nearly as bad before they did the shim. While it was in I had my first free oil change, tire rotation and inspection. They used Dexos spec 0W20 oil and a GM filter. Filled it perfectly. I'm very satisfied with my dealership. Im always hesitant when I hear the horror stories people post on here about crappy dealers.

I can tell you Fox Valley Buick GMC in St. Charles, IL is top notch. And I'd recommend them to anyone in the Chicago area.

I'm done obsessing on this issue now. The truck is running top notch, and I cant expect a huge V8 to not cause even a slight vibration.

MyFavTruck, my build date is August 2013.

Dnt · March 23, 2014

I agree with you, it can turn into an obsession, my water in the cup test went well no shaking of the water. Now I have to make myself forget about it. It is like you say a V8 power beast truck. Let it growl a bit, it is its nature. What was that old fable about the frog and the scorpion?