Shake or Vibration Issues

14SilverLTZ · April 17, 2014

Nothing in the center console or floor. Just the passenger seat. And if I have the baby seat in the back you can see it shake a little. When baby is in the seat it doesn't shake. Kinda weird. Mostly since it comes and goes at random.

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Aboothlsu · April 17, 2014

My truck is @ the shop now. They're putting in the new (2nd) shaft which has a new part # and if that don't work, the rear end is next on the list they said

My rear end is on the way. Should be in today or tomorrow. Trucks been in the shop 10 days and counting. Hopefully this fixes the problem.

anthony2558 · April 17, 2014

Its crazy that were replacing rear ends now. I really hope GM gets to the bottom of all this. Hopefully it works for you.

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pm26 · April 18, 2014

My rear end is on the way. Should be in today or tomorrow. Trucks been in the shop 10 days and counting. Hopefully this fixes the problem.

And if it does not?

20L8TSierra24 · April 19, 2014

GM gets a certified letter from the attorney general's office giving them one more chance to fix it... Its the third time mine is there for this reason... Dealer is really working on it for me though. They called me yesterday and said it was the same with newer drive shaft and said on Monday that they would get into the rear end. The tech called GM and they told him to check the backlash on the ring and pinion and go from there. If the backlash is more then spec, my rear end will be ordered on Monday.

Aboothlsu · April 19, 2014

And if it does not?

The dealership has been fantastic to this point and said that they will not give it back to me until it's fixed. I'm hoping this means a new truck or refund if they can't fix it. If not lemon law and an F250. i hope ot doesnt come to tbat point.

Aboothlsu · April 19, 2014

GM gets a certified letter from the attorney general's office giving them one more chance to fix it... Its the third time mine is there for this reason... Dealer is really working on it for me though. They called me yesterday and said it was the same with newer drive shaft and said on Monday that they would get into the rear end. The tech called GM and they told him to check the backlash on the ring and pinion and go from there. If the backlash is more then spec, my rear end will be ordered on Monday.

same thing they were told to check before ordering mine. Apparently it was out of spec

07Serria · April 21, 2014

Are double cabs having this problem as well, or is it only crew cab models?

Chappy 1901 · April 21, 2014

07Serria- I started with a 2014 All Terrain double cab with the 3:08 rear end and the 5.3l That vibrated terrible. The dealer had that truck for over 30 days trying to figure out what was wrong. I owned it a total of aprox 90 days. See my earlier posts. They would take new doubles off the lot and they would do the same vibration. It's a problem and a BIG one!

Chappy 1901 · April 21, 2014

Guys- It's been a while since I posted that I "found the cure" on my truck by cutting my plastic panels off the bottom. Guess what?!?! Yep, it's baaaack..... Piss me off! I'm at the mileage now where my other truck was. (2000). I noticed something interesting last Friday. Went to a concert with some friends and my buddy and I were in front and the girls were riding in the back seats. (Insert joke(s) here) The vibration was more aggressive and sustained. (Again, insert joke(s) here). LOL. Anyway, the vib is back and I alerted the dealer but haven't taken it to them as I know they know no cure. I encourage people to keep posting and documenting what their experiences are with their vib issue. My thought is, this could be great documentation for a class action. I have a meeting with my lawyer this week to discuss just that. I am frustrated with GM for the lack of acknowledgment of this issue. What I really don't understand is how random this issue is. Random weight, speed, conditions, etc. All the best and have a great week!

2strokesmoke · April 21, 2014

Ok it has been a while since I posted my first post, I have been busy trying to figure this thing out.

First off these trucks have a few issues, tires, driveshaft, rear end gear lash out of spec.... and the latest culprit might be the axles might not be at a 90deg to pinion gear? Lets just say they are mating 1-2degree off that would cause the pinion gear to chatter and cause vibration up to front drive system. Some have said that a new rearend has fixed there vibration issues. If this is true and axle is out they will wear smoother as they comform to pinion gear but now the gear lash will be greater also in time requiring more shims to correct.

When any change of weight distribution occurs in truck this might correct vibration or increase depending on the angle that is affected.

I filmed my pinion and driveshaft area with a go pro camera, and I noticed that my driveshaft has too much forward to reverse play also know as gear slop! When driveshaft torque is applied I wittnessed my pinion gear turning then binding somewhat as it turned and applied torque to axles. It turned and then binded, and move somemore.

This might be why they are telling the dealers to check pinion to axle lash clearances.

If they are out and axle is not 100% right angle to pinion lash will only get worse until shimming is needed...this takes a while for gears too wear and conform. Best sollution for GMC is a rear end swap out to correct problem.

I encourage folks to have the rear end checked for oneven break in wear on axle or pinion gear. This is only 1 problem that might be your problem, tires and driveshaft issues are known culprits also.

I encourage filming your axle at pinion gear and rotate your truck from forward to reverse to see this slop and its effect on the pinion rotation.

Just saying my 2cents worth

2strokesmoke · April 21, 2014

Maybe the axle suppliers tools were out of alignment or quality control went south "no pun intended".

After all bad machining is number 1 reject for rotational mass failures or vibrations followed by bad engineering or design.

Gmc announced a change this year to their axle size too accommodate more better towing numbers. In the past only vibrations known from old design was driveshaft out of spec or imbalanced properly....and the known " clunk " from forward to revere gear slop... same tranny same front differentially, but different rear end different driveshaft mainly!

Whinning noises are a tell tale sign gears might not be running / mating properly in my humble opinion.

Start by lifting and removing tires from vehical, and run the vehical while on lift to speed that causes known vibration. If truck still has some vibration then your tires can be ruled out as the only culprit!

Keep searching and sharing info, we will get this figured out soon enough even if gmc dont want us to find the issue.

Thxs

20L8TSierra24 · April 21, 2014

Dealer called this morning and said they're changing out the rear axle (differential). Guess the lash was out of spec... I really hope this helps, not just for us, but for the dealers like mine who are going out of their way to help customers out... This really sucks because my 14 Impala has been flawless so far... All I can say my truck in the shop so much has turned a couple of my friends away.. (for now). American axle really screwed up for so many of these rear ends getting swapped out...

2strokesmoke · April 21, 2014

20Bowtie14

What exactly were you feeling and at what speed did vibration start, and what gear was tranny in when it starts.

My truck starts to vibrate and shake around 40-50 miles an hour and gets better above that speed.

My tranny s gear is in the 4th when it starts to shake.

Getting Gmc involved now to have the rearend checked out, after my tires were replaced, my trucks vibration has gotten better but not gone yet, rearend check next culprit.

Thxs

Edited April 21, 2014 by 2strokesmoke

20L8TSierra24 · April 21, 2014

20Bowtie14

What exactly were you feeling and at what speed did vibration start, and what gear was tranny in when it starts.

My truck starts to vibrate and shake around 40-50 miles an hour and gets better above that speed.

My tranny s gear is in the 4th when it starts to shake.

Getting Gmc involved now to have the rearend checked out, after my tires were replaced, my trucks vibration has gotten better but not gone yet, rearend check next culprit.

Thxs

At the beginning I only noticed it from 72-80 or so on the highway. I had 2 tires replaced and it got much better but was still there. Then the dealer replaced the driveshaft twice just to make sure because they had 2 different part numbers but it still was there. In between they took wheels and tires off another truck and was worse with the smaller rims. They also balanced my wheels at leat a 1/2 dozen times... Before I took the truck back I found some smooth road and I did notice it between 45-55 but barely. Upon heavy acceleration from a stop I noticed it as well in the rear end. I'll keep everyone posted in the outcome of the new rear end. Hope this is a bit of hope for many of us on here...