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Posted

This is the e-mail I received from today from GM....

 

 

I also received an update from the District Manager over the dealership. He

stated that he was the driver of your vehicle yesterday, and he provided the

following information:

 

"I drove this truck today for vibration complaint. I did not feel any abnormal

vibration. We program the transmission to get the best possible fuel mileage,

and when we do that the torque converter is locked up in the highest gear

possible for that speed. Sometimes this causes the engine to lug (strain to pull

the truck). When that happens, you get vibration out of the driveline. When you

depress the throttle and give the engine more gas, the transmission will down

shift and the vibration goes away. Also with a stiff frame and suspension, along

with the short wheel base, you feel more road imperfections.

 

I have concluded this vehicle is performing normally and nothing else needs to

be done."

 

If you feel there is still a concern present with your vehicle, I would suggest

diagnosis by another GM dealer for a second opinion. In regards to a ride-along

with the service technician, that has to be noted and requested when your

appointment is set, as each dealer is independently owned and operated.

 

 

...and, you expected a different result from a GM District Manager?

Posted

 

CONGRATULATIONS!

 

Waiitng to get the same letter myself. Hopefully soon.

 

How long did it take and did you go BBB or straight to Lemon Law?

 

It only took a couple of weeks after contacting the BBB. This is the required first step for Lemon Law cases in my state.

Posted

^ Wow, a couple weeks after you contacted BBB? Thats fast.

 

I went back and read your posts about this issue. You had an assistant service manager that worked with you and agreed there was a problem with your truck and actually tried to fix it. After several tries, Im assuming he then told GM that he couldnt fix it?

 

THATS the difference in dealing with GM on this or any other issue.

 

I brought up the vibe with my selling dealer on DAY 2 of ownership, July 2014, filed with BBB in early Oct, and am STILL fighting with GM about it. I finally hired an attorney.

 

My dealership service manager has said all along, no vibration, operating as designed. THAT has been the hurdle to overcome.

 

Short version. If your dealer helps, GM will fast track a buyback or trade assist. If your dealer doesnt help, its an uphill battle.

Posted

Has there been issues with the 2015's? I'm now in the position I need to find a new vehicle...

yes all the 2015's have the same vibration issues.

 

I think the 2015's finally got rid of the HD radios that don't work so they don't have those issues anymore but otherwise the 2015's have all the same issues as the 2014's

Posted

Has there been issues with the 2015's? I'm now in the position I need to find a new vehicle...

There a lot of new GM trucks that do not have this issue. That said I would wait till spring if possible.

Posted

FWIW, I'd like to share an interesting conversation I had this week with a family member that happens to be a GM tech.

 

I asked if he had seen many new trucks with vibration complaints. He told me he currently has a '14 on a lift waiting on a complete rear axle.

 

Unable to diagnose the cause of the vibration, he contacted a regional field engineer that he knows very well and asked for assistance in diagnosing the issue. The field engineer instructed him to check the ring and pinion specs., that there is a known issue with pinion gear input shafts being out of spec.

 

After receiving this info it was determined that the vibration was in fact caused by "out of spec" ring and pinion tolerances, more specifically that rotating the gears would create a bind or a zero backlash situation.

 

GM authorized replacement with a complete rear axle assembly. He then said the replacement axle assembly that was received was worse than the original and could not be installed.

 

Not sure what has happened since. If I get more info I'll definitely update.

  • Like 2
Posted

Well last Tuesday I got the call from Service Director,
They are basically at the end of what GM engineers have suggested.

I truly believe that my Service Director has done every thing conceivable along
with the " IDEAS " supplied by the GM engineering and technical staff.

So after countless tire road force procedures and a new set of Michelin's and another round
of road forcing them, and new pinion gear there are absolutely no changers in the vibration
of my NEW 2014 K-1500. When I arrived my truck had a set of stock OEM wheels and tires
(bridgstone) the same route was taken and the exact same issue was very noticeable.

Once the heaviest vibration began (@ 73mph) I looked over at the Service Director saying nothing
he then promptly said I'll have to get an engineer out to drive it, and that might take some time.

The ' Stock Unit ' that has less then a 100 miles on it is also experiencing the very same issues
as well as the loaner truck I was using a 2014 C-1500 Double Cab with a 5.3 V-8 with 710 miles.

After all of the procedure's that have been preformed on my truck I can safely say it's not a
tire or wheel issue and obviously not the pinion although some play was noted on the original
due to excessive metal shavings...or so I was told as I'm still waiting on my paperwork with
the exact details.

While I wait for the GM engineers to make a guest appearance, I'm having two major concerns
(1) This being a SAFETY ISSUE, I'd really hate to be the cause of something to happen to someone
else if this truck become more unstable at the noted highway speeds then it already is now.
(2) I'm by no means an engineer or pretend to be. However my vast experience with vehicles and
some round table chats with people in the industry a few ideas have came up,
I'll reserve our thoughts and ideas until I have all of my paperwork and given the GM engineer a shot at a ride & drive.

The good news is I had my truck for Thanksgiving !
Even though I feel unsafe at highway speeds and it's screws up my proven break-in procedure.

Posted

I'm really worried about my truck now after reading all the good and bad stuff about the dealers service departments. Well I'm worried more about the bad Expreinces. My 2014 Denali 4WD 6.2L has got the vibrations starting at around 65 and up its the worst around 75 to 80. I have almost 8K miles on it now taking it in Tuesday for the second time to try to find a fix ?

Posted

yes all the 2015's have the same vibration issues.

 

I think the 2015's finally got rid of the HD radios that don't work so they don't have those issues anymore but otherwise the 2015's have all the same issues as the 2014's

Just keep buying them! This way GM has no incentive whatsoever to fix the problem.

  • Like 1
Posted (edited)

I'm really worried about my truck now after reading all the good and bad stuff about the dealers service departments. Well I'm worried more about the bad Expreinces. My 2014 Denali 4WD 6.2L has got the vibrations starting at around 65 and up its the worst around 75 to 80. I have almost 8K miles on it now taking it in Tuesday for the second time to try to find a fix

This is one of the reasons why 2014/15 owners without the vibration or shake should be "knocking on wood" everyday.

Edited by 14LTZZ71
  • Like 1
Posted

I have a GM engineer coming out on December 10th to diagnose my shudder from launch when towing and now I have developed the dreaded random vibration . I almost traded it in today on a 2014 F150 but I just couldn't take a $4,000 hit yet. My dealer has been good so I am giving it one last shot to make it right. If they don't get my problems fixed I will go the buy back route.

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