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Posted

My first truck was that bad... After they replaced pretty much everything rear or the tranny, including the rear end, it never got any better... Good luck

  • Like 1
Posted

Did you get a new truck?

GM and my dealer ended up buying it back and now I have an LTZ Z71. My first was an LT 4x4. That truck had literally everything replaced and no fix. GM gave me "Trade in assistance" along with the 35 K the dealer gave me. I put a new set of tires on and its as smooth as glass now. I ended up paying like $1200 difference for the LTZ otd.
Posted

I have an idea... Someone put their truck in M5 and go cruising down the highway at 75 and see if it goes away. This would eliminate the 6th gear which is where most of us are feeling it on the highway, and see if its a tranny problem.

Posted

I'll try that next time I hit the highway. In the meantime I will just try to not think about it . Kinda ruins the entire weekend after u pick up your new truck on Friday after it was in the shop for the third time in the past month and it's not any better.

Posted

Although I have not experienced the problem with my truck I did with another motor that wasn't running on all cylinders. Could it be the AFM that's not letting the motor run on all 8 cylinders?

 

Sent from my Nexus 7 using Tapatalk

Posted

Or timing off via screwed up software?

 

Sent from my Nexus 7 using Tapatalk

  • Like 1
Posted (edited)

Mine isn't that bad...but bad enought to be annoying. I've tried stepping on it a bit and it does it in V8 mode too....even after it's downshifted to another gear. I think I even tried shifting into Neutral and coasting over 70 and it did it. It seems not to be AFM related, or transmission related, at least with my truck. Completly dependent on rolling speed...over 70 and for a few miles before it starts happening. The warmer out, the worse it is...the higher the tire presure, the worse it is. Yesterday we took a family day and drove backroads up to 5o-55 to the beach, shopping, and out to eat. It was a nice day and the truck drove beautifully. We drove something like 92 miles, and averaged 21.4 MPG! If this truck wasn't so damn nice looking, and got such great fuel economy it'd be in big trouble LOL! I was set to buy tires and an alignment...but now I'm taking it in Tuesday and letting them keep it a while and see what they find. You have to try that first and who knows...they may fix it. This CANT be a mystery forever. I dont think there's ever been a vehicle made that an issue with it remains a mystery to this day. They'll figure it out. The service manager I spoke with did say they've seen alot of them coming in for vibration, and it seems like both GY and Michelin tires are on trucks that vibrate. He did say recently, they had to shim a rear end on one truck, and an engine mount in another to fix high speed vibration. He seems like a real nice guy, who wants to get to the bottom of your problem so that's promising. We'll see what they discover this week.

Edited by MJFlores
Posted

Let me just say this, there is enough people out there with this issue that GM must have an idea of what is going on!

Are they not doing anything about this? Or is it because it will be too costly to fix all these trucks now, and it is only a vibration right.

Everybody you need to report it to your local government agency like NHTSA with concerns that new vehicle s should not vibrate, and it is not safe!

Also report these tires, they are not right with the sidewalls deforming this soon.

Speak up people, and enough of us they will have to investigate our concerns folks.

Then we may learn the truth about these trucks.

I had enough lies, I have started legal actions to correct my vibration!

I also reported my concerns over safety with this truck too.

Posted

Well as I was researching the vibration issue some more I decided to make a quick video of my idle vibration . If someone who has a smooth riding truck could create one to show it is not just engine related that would be cool! So here is my truck idle with some vibration .

 

 

Posted

Do you think some of your shaking issues could be related to the lift kit on your truck? And do you really think comparing it to an Escape is a fair comparison?

 

Mike

  • Like 1
Posted

GM and my dealer ended up buying it back and now I have an LTZ Z71. My first was an LT 4x4. That truck had literally everything replaced and no fix. GM gave me "Trade in assistance" along with the 35 K the dealer gave me. I put a new set of tires on and its as smooth as glass now. I ended up paying like $1200 difference for the LTZ otd.

 

Glad you got a new truck! And glad your new one is vibration free!

Posted

Do you think some of your shaking issues could be related to the lift kit on your truck? And do you really think comparing it to an Escape is a fair comparison?

 

Mike

Well I don't have a spare 60k $ truck to compare it to in my possession so I'm working with what I got :) a 25k$ Ford . That's why I asked if someone like yourself could post one . Did you read that part?

Posted

And also I had a 2011 with the same lift and tires/ rim size and it did not have any issues with this much vibration. but to answer your question I have considered the lift to be part of the problem but the dealer has not found anything wrong with the lift . Had a new drive shaft installed that helped a little and the tires force balanced twice . My salesman said the others he has sold with exact same lift and wheel combo are not having the problems I am ...

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