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Posted

Nope, Just calling it like I see it. Thanks!

Same here....

Posted (edited)

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

 

yep, its such a fake transparent attempt to deceive its comical really, but then what else can they do, they are not "really" trying to fix this, they are just bidding their time until they can sell off all the 14's and 15's and then move on to a different design for the 16's

Edited by keakar
  • Like 1
Posted

I am a GSM for a Chevrolet/Subaru/Chrysler dealership. After going away from Chevy back in 09 to Ram I was tired of the poor quality control and just picked up a 15 Rally 2 Edition. I did a dealer trade as we didn't have one in stock, and drove an LT ext cab Chevy down. That truck rode like a dream. No vibes, shakes, nothing. Perfect.

 

I hop in mine and head back and what do you know, the dreaded vibes. It generally happens between 60-75 but has occured as low as 50 on random occasions. As with others here, it is not consistent (changes based on throttle input, load, etc). It's the worst a cruising speed though and can shake very bad through the wheel. I bring it back and have my shop do a road force balance which accomplishes nothing.

 

I ended up calling our dealer Chevy tech line today to see what they had to say and they mentioned they lowered the road force balance limit from 25 to 15. I doubt that's going to change anything but it's worth noting. He also mentioned that there have been quite a few rear ends replaced due to excessive lash that they felt were contributing to the vibration. That certainly seems plausible as it changes depending on load which could definitely point to that as a potential culprit.

Posted

kchaggins ... I have driven a '99 Silverado LT extended cab 5.3 3.42 Z-71 for 14 years and 300,000 miles... still own it and still rides like a dream. Replaced it with a new 2014 Silverado LT Double Cab 5.3 3.08 gears Z-71 and wish I never did. This truck shimmies, shakes, vibrates all the issues you see on these post. GM has "looked" at it more than several times, and found it to be 'driving as designed'. IF this is true, GM design engineers should be fired.

As a side note, I am starting to think some of the vibrations are coming from the transfer case. When switching into 4 Wheel Auto (at high speeds), there is gear noise and a high pitched "whining" that is very noticeable.

 

Either way, this could be an excellent truck. The vibrations just need to be figured out!

Thanks.

Posted

Editing post. I disabled AFM (v4) a few days ago and after my morning commute today I can surely confirm I still get the random skakes at higher speeds that come and go. The vibration I was feeling in the gas petal I thought at first seemed less intense with AFM off but after today I don't think it is. I also feel a steering wheel vibration more so than I did before my truck was in for service last week. Seems like maybe them remounting and rebalancing the tire could have made it worse. Somewhat frustrating. Does this amount of weights in the wheels fall into the normal range? attachicon.gif20150609_074813-1.jpg

 

I have 9 weights on the left rear wheel of my truck after a road force balance.

Posted

I have had my road forced balance but the tires and rims were never broke down.

 

I actually have a wheel that has 4 weights on the outside edge and 1 weight 180 degrees opposite on the inside edge, I was always under the assumption that weights should not be directly opposite each other

Posted

 

I have 9 weights on the left rear wheel of my truck after a road force balance.

It looks like that's a total of 2.25 ounces which isn't too much, just looks like a lot because there is such a long strip. I believe anything under 3oz a wheel is pretty good, obviously the lower the better.

 

 

Sent from my iPhone using Tapatalk

Posted

I have had my road forced balance but the tires and rims were never broke down.

 

I actually have a wheel that has 4 weights on the outside edge and 1 weight 180 degrees opposite on the inside edge, I was always under the assumption that weights should not be directly opposite each other

Actually, it's completely possible to need weights opposite each other when doing a proper dynamic (2 plane) balance. The machine measures the unbalance at 2 separate planes, in this case, the inside bead and outside bead. There can absolutely be unbalance 180 degrees apart, especially with cast metal like aluminum or definitely in rubber compounds like tires. In castings, porosity can form during the casting process. This results in air bubbles or voids, which of course are lighter then the base material. And hence, and unbalance presents itself. And, nothing to prevent the same thing from happening 180 degrees on the other plane. And when you add the tire to the wheel, well all hell can break loose!

 

That said, it certainly speaks to the quality of the tire, the wheel, and/or the balance machine operator. Because, there is also the possibility that the wheel had some unbalance on the outside bead and the tire some on the inside bead (as it was mounted). A proper sequence in Road Force balancing would actually detect that, and have the tire swapped around and mounted such as to cancel the wheels outer bead imbalance. At least as much as it could. And the rest, by weights.

 

So, there is more to it.

  • Like 1
Posted

Mine was indeed a bent rim. Had to have happened before I bought it. I don't remember hitting anything that would have impacted it that much. Smooth riding now!

Posted

About 200 miles on new Firestones, brought it back in for shaking on highway. Wheels were allegedly taken off rims, re mounted and re balanced. Only took city roads home so unable to tell if the shaking is prevalent yet....I'm not optimistic.

 

 

Sent from my iPhone

Posted

Truck still in the shop they put brand new Goodyear sra still didn't fix it. Now putting all new shocks

Posted

I have a 2015 4x4 Silverardo 1500 regular cab, 8 ft bed with just over 2k miles now. Just after 500 miles, I started to notice a vibration right at 70mph. At 65 didn't notice at all, and at 75, started going away.

 

Brought to dealer here and they Load balanced and found two bad tires from factory. They replaced and I'd say 75% of the vibration has gone away. Thus making it shall I say less offensive.

 

Wade

Posted

It looks like that's a total of 2.25 ounces which isn't too much, just looks like a lot because there is such a long strip. I believe anything under 3oz a wheel is pretty good, obviously the lower the better.

 

 

Sent from my iPhone using Tapatalk

How so? There is 5, 10, 30, 35 and 40oz weights, how do you come up with 2.25 oz?? He didnt specify what type he has on there. 3oz is excessive.

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