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Posted

So, I've filed a complaint with BBB. GM contacted me and sent me to a second dealership as the first one basically told me to pound sand once they got wind of the BBB complaint. With that said, the second dealership replaced all 4 stock Continental tires with Firestone tires.

I like the handling and profile better of the Firestones, but the shaking continues; actually partially worse at slower speeds (60-70) as the Conti's were worse at around 70-80.

Back to dealer tomorrow.

Sent from my iPhone

So, the fact that changing tire brand changed the response (ie the speed/frequency) of the vibration certainly points to the tires. Now, that can mean the tires are the cause. Or, it can mean the tires are simply part of the system that is responsive. Changing tires can change the mass and /or the stiffness of the tire. Both are key parameters in the natural frequency of any system. Natural frequency will be the frequency a system resonants at. So, any disturbance at the natural frequency usually results in a resonant condition (meaning an amplification of the initial disturbance.

 

Disturbance = residual unbalance in the tires! wheels, hubs, etc. (there will ALWAYS be some residual unbalance left over, even after the best balancing job).

 

This is sounding more and more like a resonant condition. Could be suspension. Could be frame. Could be body. It's all one, interconnected system.

 

May not be an easy fix for the folks at GM.

 

Still, has anyone tried aftermarket shocks? I seem recall some discussion about that.

Posted

Mine is in today. They are starting with a road force balance and an alignment. I have also provided them with a copy of the TechLink bulletin regarding V6 to V4 vibration. The gist of that procedure is to unbolt the exhaust from the manifold and re-torque to installation procedures. I have read at least one post that this seemed to cure the AFM problem.

 

I will update if anything seemed to help.

 

I questioned whether the service techs use any vibration tools - pico or oscilloscope - and the response was that yes they do but do not really like them because the roads are so bad that the results are skewed! (i.e. don't know how to use them correctly)

Posted

I own a 2014 Silverado High Country. I am also experiencing the V8 to V4 “shake, rattle and roll” and after reading hundreds of post on several forums concerning the matter, got worked up over a “defect” that is not really a defect. Yep, after figuring it out myself it become apparent the truck “IS” operating within design perimeters, hence, dealerships’ assessment as “normal” regarding the “shake, rattle and roll”. I took my truck to the dealer and complained and now feel less than smart for not doing the research before taking action. At the risk of alienating someone this is how I see things.

 

1. To be very honest, other than wanting perfection, this issue doesn’t pass the “so what” test. It’s not a show stopper just an annoyance. Silverado is a truck and when you change the power to weight ratio of 3 tons of truck while driving, things are going to be less than perfect but mpg will increase.

 

2. Heck, I can count the times I’ve ever seen the V4 mode because I almost never consistently drive within that range and most likely accelerating beyond it. I believe most of you are too; with your foot to the floor.

 

3. When you buy a 3 ton truck with a 6.2L engine…well, obviously “mpg” is of no concern. And other than appeasement and the perception of good customer support, I believe GM may have come to the same conclusion being more concerned with gearing up for 2016 than fixing something that is a “non-defect”. As Blade would say, “someone always got to skate uphill”.

 

4. If I was so concerned about mpg a small foreign pickup would have been sufficient instead of one of the best and biggest American truck ever made.

 

5. One man’s trash is another man’s treasure. If you throw away a truck because of this matter someone else will surely prophet! And when you take your truck to the dealership for something like this they might screw something else up just looking for something that is not a problem

 

6. Understand this, I believe the whole matter is “someone” else’s agenda, definitely not something that concerns me.

 

I guess this is GMs way of doing a little damage control. Lol, what a joke!!

Posted

2014 double cab 5.3 LTZ 20" Continentals

 

I had my truck in a total of three times for the vibration at 70MPH. First two times they road force balanced the tires and moved them around.. Finally they replaced 2 tires (Continental's) on the third visit and the vibration seems to be gone... The dealer was excellent and I didn't even buy the truck from them...

  • Like 1
Posted

2014 5.3 3.42 20" Continentals 17,000 miles. My truck rode like butter, better than my sisters caddy till I got about 13,000 miles on it. Started vibrating at around 73mph (not all the time). Brought it in said I had 2 bad tires,had to pay 40% for 2 new tires, still vibrates. Been trying to figure out when it happens. I swear it seems better when I have a full tank of gas. Anyone else notice this?

Posted

I liked the ride of the Conti's better, the handling of the stiffer Firestones better, however still shakes 70-82ish. In for 4th visit. Fingers crossed

 

 

Sent from my iPhone

So, the fact that changing tire brand changed the response (ie the speed/frequency) of the vibration certainly points to the tires. Now, that can mean the tires are the cause. Or, it can mean the tires are simply part of the system that is responsive. Changing tires can change the mass and /or the stiffness of the tire. Both are key parameters in the natural frequency of any system. Natural frequency will be the frequency a system resonants at. So, any disturbance at the natural frequency usually results in a resonant condition (meaning an amplification of the initial disturbance.

 

Disturbance = residual unbalance in the tires! wheels, hubs, etc. (there will ALWAYS be some residual unbalance left over, even after the best balancing job).

 

This is sounding more and more like a resonant condition. Could be suspension. Could be frame. Could be body. It's all one, interconnected system.

 

May not be an easy fix for the folks at GM.

 

Still, has anyone tried aftermarket shocks? I seem recall some discussion about that.

Really good points.

 

 

Sent from my iPhone

Posted

I took my truck in for its second free oil change and I stayed outside to make sure the kid doing it was actually gonna rotate the tires. He did rotate them and put in 8qts of oil per the new bulletin on that. Took my truck out to the interstate and accelerated hard to 80 mph and stayed in the 70-80 mph range. Truck is not vibrating near as bad as it did when new, just a very slight vibration in the low 70's but hardly noticeable. I am pretty sure my vibe problem is related to these crappy GY tires

Have 265/65-18 Good Year SRA's and feel slight vibration 75 mph. Had truck serviced a few weeks ago and noticed 38 psi, and said to be filled with Nitrogen. Will adjusting down to recommended 35 make any difference? next set will be Michelins

Posted

I have played with the PSI a little bit to see if that makes a difference but honestly I am rarely on the interstate in this truck, mostly on county roads and 4-lanes with 55 mph speed limits. I did notice that back in the winter the truck vibrated more when I first left the house and as the tires warmed up things got better. The vibration I randomly get at 70-80 mph is what stumps me. Doesn't do it everytime so that tells me it is transmission/torque converter or something of the like. I was noticing every vibration in my chevy but have quit doing that after riding around in my wifes Grand Cherokee. That thing is smooth as it can be but the water in bottles do vibrate somewhat, about the same as my chevy. I feel bad for the ones who have the really bad vibes but I think alot of people are complaining about more slight vibrations which is probably a tire or wheel slightly out of balance or some of driveline component that is slightly out of spec.

Posted

Back from service report.

 

Road force balance done

Alignment done - out of spec positive caster on right front

 

The Techlink article for V6-V4 AFM of removing exhaust from manifold - not done - GM does not recognize Techlink

 

So, steering wheel feels better (not as much vibration) but still odd vibrations whole truck on the highway 70 to 80.

 

I will let them know still not satisfied that the issue has been resolved.

  • Like 1
Posted

Although it's not going to be fixed until later in the week, turns out I have a bent rim. It must have happened between transferring to the three dealers before it came to me for purchase. They are ordering a rim, hope to have it come in tomorrow, then hoping it's smooth as silk from there. If that's the case, way better scenario than I anticipated.

Posted

Mine must have heard me call the dealership last night. Today's commute to and from work on the highway was vibration free. I really don't understand how random the vibrations are.

Posted (edited)

Get my truck back tomorrow hopefully it fixes the problem. There replacing the good years with ContinentalCROSSCONTACT LX20. Will report back if it fixed it. Again this is for a 75mph and up vibration issues felt in the seats. Was going to upgrade to a Michelin and he told me there having just about as much vibration issues as the good years did. So hoping for the best.

 

 

Update didn't get the truck back today. There putting brand new Goodyear sra back on it again. They ordered 12 of them and picking the best 4. Putting back on sra because of some gov rule saying the continental was a suv tire and not for a 4wd.

Edited by JC84
Posted

My theory is that the natural frequency (or frequencies) of the new stiffer frame is well matched for an out of balance tire, driveline, or even rough engine in V-4 mode. Until frame vibration dampers (like Dodge uses) are added, these trucks are going to always have this problem. Slightly worn and out of balance tire - vibration, engine running a little rough from bad gas - vibration, tight u-joints - lots of vibration, etc... Dampers are an inexpensive and tried solution and will fix the problem, GM just needs to admit that there is one. I wonder how much money they have spent on this compared to actually fixing the problem?

  • Like 2
Posted (edited)

I went through hell with my truck I did the bbb process got no where wrote gm nothing went to the dealer many times nothing I talked to a attorney he would ask for a work order stating it wasn't the tires or alignment so I did he called back after I sent it said that he needed the Tec to state the number of years he has been a mechanic and it was not normal for that model of truck to vibrate that was the end gm won I hope they are happy here's what I did to mine and its smooth going all the way til it shuts down I have drove 1500 miles now and no problems I put michilen tires on it helped out but didn't fix it then I put Gabriel ultra shocks on the rear got better yet took the drive shaft out to have it balanced by a professional it had 30 thousandths run out they fixed my drive shaft 65$ Some people say that the drive shaft vibration is at speeds of 40 to 50 but it made a big difference in my truck at 70+ That took care of all the shaking in truck that could be felt in the seat and center console, the vibration in the steering wheel and gas pedal have went away at 18000 miles it's sad that I couldn't get gm to fix my truck I don't have adjustable pedals on mine but for a while I cut little foam squares about a 1/4in thick and put them under the right corner of the plastic plate the gas pedal and bracket are mounted to to help dampen the vibration but I have since took them out and it is fine I'm not saying that it's going to fix every ones truck but I think any info any one has could help others it drove me crazy my wife was so happy when I told her its fixed and I now love my truck

Edited by 300ktm
Posted

I went through hell with my truck I did the bbb process got no where wrote gm nothing went to the dealer many times nothing I talked to a attorney he would ask for a work order stating it wasn't the tires or alignment so I did he called back after I sent it said that he needed the Tec to state the number of years he has been a mechanic and it was not normal for that model of truck to vibrate that was the end gm won I hope they are happy here's what I did to mine and its smooth going all the way til it shuts down I have drove 1500 miles now and no problems I put michilen tires on it helped out but didn't fix it then I put Gabriel ultra shocks on the rear got better yet took the drive shaft out to have it balanced by a professional it had 30 thousandths run out they fixed my drive shaft 65$ Some people say that the drive shaft vibration is at speeds of 40 to 50 but it made a big difference in my truck at 70+ That took care of all the shaking in truck that could be felt in the seat and center console, the vibration in the steering wheel and gas pedal have went away at 18000 miles it's sad that I couldn't get gm to fix my truck I don't have adjustable pedals on mine but for a while I cut little foam squares about a 1/4in thick and put them under the right corner of the plastic plate the gas pedal and bracket are mounted to to help dampen the vibration but I have since took them out and it is fine I'm not saying that it's going to fix every ones truck but I think any info any one has could help others it drove me crazy my wife was so happy when I told her its fixed and I now love my truck

 

Punctuation Please!

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