Shake or Vibration Issues

[abominable z71]

I already got a hold of some used cv axels off ebay should be here in a week or less. According to my research gm has been using the same 33 spline outer stub shaft since 1999, the axles themselves have changed as a whole, mainly in their overall lengths and possibly the inner joint but the gm part number for the outer joint 22928970 is the same for trucks, suv's and avalanches from 1999 on. But it is the internet so I'll know for sure when they show up.

[14silverado4.3]

I already got a hold of some used cv axels off ebay should be here in a week or less. According to my research gm has been using the same 33 spline outer stub shaft since 1999, the axles themselves have changed as a whole, mainly in their overall lengths and possibly the inner joint but the gm part number for the outer joint 22928970 is the same for trucks, suv's and avalanches from 1999 on. But it is the internet so I'll know for sure when they show up.

Ab, when you find the solution are you going to sell it to GM?

[mikegmi2]

i have a vibration on hard acceleration from a dead stop also..

This is another issue...likely having the dealership take a look at the engine mounts will fix this. Many trucks need engine mounts to be shimmed. They had to do this on one of mine, and it did fix the issue.

[mikegmi2]

 

I have been experimenting with this over the last few days and have found that the driveline angles are off. I have the same exact symptom as you. Other than this one issue the truck rides perfectly smooth. Tires are true and there is no shake at all at highway speeds. But when I am decelerating with no brakes there is a vibration that is felt and is accompanied with a roaring sound like a badly cupped tire except it oscilates more. This vibration is worst from approximately 52mph down to 40mph. I can also feel this in the steering wheel and seat. Now here is the kicker if I shim the rear axle and angle it up, the vibration diminishes. Untouched, the vibration that I feel is about a 7 but when I shim the rear axle its about a 3. This slight vibration never totally goes away I think its the pinion/ring gear backlash but thats not the only issue. The slack in the rear end is agitated overtime by the bad driveline angles and this causes increased wear. This with also increase wear on U-Joints, bearings and seals. If the rear axle is replaced and the pinion angle, along with the slip yolk angle are not corrected and phased correctly iwth the driveshaft, this will be a recurring issue. I am getting a second opinion from an independent 4 wheel drive shop and will share this information.

I've literally gone through this 1 time before, and am going through it a second time right now. They will replace the entire rear axle assembly, and realign everything. With my first truck it completely fixed the issue, perfectly smooth when decelerating.

 

This is a serious issue...everyone should check for noise/vibration when decelerating, specifically between 50-40mph!

[Trevor01]

After 5 months of fighting with GM, they are offering me a buyback or swap to a 2016. I would say they know there is problems with this platform.

[XYZ]

My regular cab 2014 Silverado has a whine coming from behind me as you drive down the road, ceases with taking your foot off the gas, returns as soon as your foot gets back into it. Easy to tell it is coming from behind your seat in a regular cab. Truck just today rolled only a little over 1900 miles, way too soon for this kind of nonsense.

[14silverado4.3]

XYZ, nice avatar!

[Jesse Davidson]

-----UPDATE-----

Ok, so these attorneys seem to be like contractors in their ability to return calls..... They don't, that is not something that I am ok with. I will be contacting a new attorney tomorrow to discuss this with him, This attorney was recommended to me by another attorney I have, I checked him out and he does appear to be good. In addition, I would like to pass along a tip I got from a lemon law attorney:

If you don't have a minimum of 3 repair attempts, don't file any claim (breach of warranty, lemon law etc.). GM will drag it out until you are out of warranty and ready to get rid of the truck. Go to your dealer and say that it has gotten worse, if it has been a certain time period of time or miles since your last visit (I don't know how long exactly) they will be obligated to check it out and you can get another documented attempt. If you attempt to file prior to having 3 documented attempts you will essentially be black balled from all GM dealers and basically never get anything done.

They also said that they are seeing more and more people who are unable to get a third repair attempt because GM is refusing. they said they have seen this before, and it is done when they don't have a diagnosis yet. SO BE AWARE, fight for yourself.

Another thing we discussed was filing other claims in small claims court, GM is legally not allowed to send attorneys there, so they have to send a rep. This way you could get a dialogue going about all of the issues and see if you can get something done out of court, as GM will NOT want to fight you in court especially with out their attorney. To do this, you would send a 30 day demand letter under chapter 93A (Massachusetts, likely different in other states) citing the costs to fix the issues, why they are liable, proof theyy are liable, under what laws/ statutes they are in violation of etc. A chapter 93A allows the plaintiff to file for double or treble (triple) damage. ie: say you paid for th upgraded all terrain tires but didn't get them, the proper tires, Bridgestone Deuller A/T RH-s will cost you lets say 1200. your claim is filed in the amount of 3600 but you offer to settle for 2600. you do this for any and all issues in a separate suit and it totals to a lot of money and opens a way for you to get a dialogue going with GM about fixing the truck.

I'm going to call another dealer tomorrow to try to get my truck in. My vibration has gotten worse especially around 43 - 54 MPH. definitely not happy with GM, but we shall see.

Good Luck Everyone

[abominable z71]

Ab, when you find the solution are you going to sell it to GM?

Right now I just want to find the source, then figure out the repair. There is something out of spec, unfortunately for me it's out of spec enough I can feel it but not enough that GM will do anything about it, such BS for a 54K dollar truck to ride worse than my very first vehicle (77 4wd K5 blazer) that was 20 years old when I started driving. I'm going to log some more hours this weekend measuring and testing different theories.

[pm26]

My regular cab 2014 Silverado has a whine coming from behind me as you drive down the road, ceases with taking your foot off the gas, returns as soon as your foot gets back into it. Easy to tell it is coming from behind your seat in a regular cab. Truck just today rolled only a little over 1900 miles, way too soon for this kind of nonsense.

I had the same problem with a 1995 Nissan hardbody pickup, 4X4, V6 extended cab, which I bought new. The rear differential developed a distinct whine at about 1500 miles that would disappear as the load was taken off the gears (i.e. taking your foot off gas). They swapped out the differential under warranty, all was quiet for about 1000 miles, then the whine started again, except this time it was there only while coasting (foot off the gas pedal). I just lived with that second differential because it did not affect anything else and the truck did not vibrate at all. That differential whine is definitely caused by improper backlash setting in gears.

 

Edited September 16, 2015 by pm26

[abominable z71]

My regular cab 2014 Silverado has a whine coming from behind me as you drive down the road, ceases with taking your foot off the gas, returns as soon as your foot gets back into it. Easy to tell it is coming from behind your seat in a regular cab. Truck just today rolled only a little over 1900 miles, way too soon for this kind of nonsense.

2wd or 4wd? I agree with pm26 sounds like lash in the ring and pinion, or improper pattern.

[MBalck]

Checked in on my truck today, as it's been in service since last Friday. I was informed they are trying a different set of wheels and tires now. The SM told me last time that he is out of ideas...they're pretty much reaching for anything at this point before they either have to do a buyback or I lemon law the truck. More to come in the next few days.

[14silverado4.3]

OK, GM gurus.

 

I did the dirty and bought new tires. BF Goodrich. It took away a lot of vibes from the truck but still there.

 

On my highway commute today, I noticed something that had been masked by the vibration from the goodyears. Set cruise at 75. The vibration is more noticeable when going uphill and downhill. The thing that was different was when it kicked down to a lower gear on the uphill, the vibration frequency sped up (increased).

 

Ideas? I am no expert and would like the dealer to check it out but want to give them some hints at what we think would make that happen. Any simple tests I can do that would confirm your idea?

 

I have been learning about driveline working angles and hearing some issues with those on stock ride heights. Could that be it?

[XYZ]

2wd or 4wd? I agree with pm26 sounds like lash in the ring and pinion, or improper pattern.

2WD....

[RoadieWingZ]

Unfortunately I think I'm part of the club experiencing the vibration problem. Picked up my new LTZ last Thursday evening and noticed vibration issues at 35 and 65+ the next day. Thought it might be due to flat spots on my tires as the vehicle had been in their inventory for 9 months and hadn't even been test driven (4mi on odometer). Decided to drive it around over the weekend but problem persists and may be slightly more noticeable. Took truck to dealer for another issue Monday morning and relayed my concern to salesman. He indicated they ask customers to drive 500 miles to give tires with flat spots a chance to resolve the flat spots. Im already at 400, but not confident it's going to miraculously clear up in 100 more miles...Sent him an email expressing concern to see if I can get them to move ahead with diagnosing/resolving while it's already in shop. Waiting to hear back.

Edited September 16, 2015 by RoadieWingZ