kcwood247

Totally agree. The fact that they mount and balanced twice is what drew me here to see if there's more going on for new GMs with vibrations around 70mph. Totally agree too. There IS an issue with SOMETHING on SOME of these trucks as noted in all the previous posts. --- "Something" and "some" are not definitive words by nature. My suggestion is to start a separate topic to collect just the data and have a moderator that has ability to remove non-data specific commentary. This was done on another forum (non-automotive) that I was on and it really helped to reduce the noise and get to the root cause. The first post was a summary / meta-data page that was periodically updated by the moderator based upon the posts. As an example, post 1 would include a summary of the findings and also state what info is being requested in the posts, and posts 2+ would just include the requested data. All other commentary would be stripped from the post. The data request might include something like: Year: Make: Model: Body Style: 2WD or 4WD: Engine: Rear Axle: Suspension Package: Other Relevant Options: Wheel Manufacturer (if not GM): Wheel Model: Wheel Diameter: Tire Manufacturer: Tire Model: Tire Width: Tire Aspect Ratio: Tire Load Rating: Tire Speed Rating: Road Forced?: Road Force Ratings (If Applicable): Build Date: Build Location: Delivery Date or Purchase Date: Symptom/Description of the Issue: Failed Fixes: Temporary Fix (Temporarily Resolved But Issue Came Back): Actual Fix (If Applicable): Opinion/feeling of where the root cause is: --- So with that said, I just couldn't help myself. I had to do the "obvious next step" and had my 2015 Yukon Denali Hunter Road Force GSP9700 tested and balanced. There is only one in the city I live in. They offered to let me watch so I obviously took them up on it. The machine is awesome. I will be getting all my wheels mount and balanced there now; it's just too precise. I feel I'd be missing out on anything else. It turns out that one of the wheel/tire assemblies was way off. It was near balanced (0.25oz off), the wheel was round, but the tire is defective and will need to be manufacturer replaced. The Road Force was 46lbs!!! And the Road Force recommendation would've only brought it down to 43lbs! So it's near definitive that that's my issue / my issue with the Yukon. Thanks for the advice everyone. Oh and I'll be back if it doesn't fix it.

If the consensus is that if I get my wheels and tires remounted and balanced for the 3rd time, but make sure they are RF balanced to the teens, and weights are applied in multiple locations (by other posts, inside and out), and it'll make my steering wheel, seats, mirrors, and center console stop vibrating/shaking at 65+mph (i.e., what everyone else is experiencing here), then I'm all for it as the next step to getting to the root cause.

I bought a 2015 GMC Yukon Denali 4WD with 6.2L, 6-speed Auto, 3.42 Rear Axle, and Magnetic Ride Control on April 5th right after it rolled off the delivery truck. It came with the Touring Package which includes Denali stamped 20" chrome wheels. The OEM tires were P275/55R-20 Continental CrossContact LX20 with EcoPlus Technology. I had other warranty related issues, but not the vibration around 70mph. Mid-May I ordered the GM CK156 (SEY) 22" Chrome Wheels along with the GM recommended associated tires - P285/45R-22 Bridgestone Dueler H/L Alenza. Received them and then had them installed Mid-June. My wife and I drive daily on a highway with a speed limit of 70mph so it's easy to go "at least" that. In the first couple of days, we noticed the vibration as shown in the water bottle test. Scheduled an appointment with our local dealership to have them look at it. We just figured we lost a wheel weight. They ended up taking the wheels/tires to another dealership that "had better equipment" to remount and balance them. I didn't make any assumptions and just figured they were doing their due diligence to fix it. Got it back the last week of June and the vibration at 70mph(ish) is still there. Googled "GM Vibrations at 70mph" and that's how I landed here. For us, I was just looking into paying another shop that I know that has a RF to test and/or fix the vibrations with the assumption that there's still something off with the 1 (or more) wheels or tires; however, after reading this "book" / forum, I'm a little concerned that there might be a much, much, bigger issue going on. Still debating next steps / how much annoyance I'm willing to put up with with being in and out of the shop vice hearing the wife "tell" me about it every time I ride with her. The only things that changed from no-vibrations to vibrations are: - Different size/weight wheels - Different tires (size, ratio, width) - Tires not mounted/balanced from factory, or, according to GM policy, from an ADI (Accessories Distributor Installer) via the LPO (Limited Promotional Option) program - More miles on the vehicle (a previous post noted that this started occurring a couple thousand miles into it) The above differences could have an impact to other vehicle components, or it could be pure coincidence and would've happened around the same time frame regardless of the wheel/tire swap. I mean come on GM....for an $80k vehicle, this shouldn't be my 7th related warranty item and 12th visit to the dealership in 3.5 months. (Just had to throw that in there so the my post would feel more related to the conversation at hand.)

Congrats! Guess it is what it is. At least you can now move on to bigger and better things, assuming it doesn't happen again.

Yep. That's it!

Right at the point where your tailgate stops and returns back down is where mine kept forcing itself up until it popped...literally like a ballon but sounding more like plastic on plastic. After watching your video, I should probably go check the point where the spoiler and roof meet to make sure it's not scratched up, dented, or whatever.

I have a 2015 Yukon Denali and had the same thing happen to me yesterday. Freaked my wife and I out. It was sitting in the sun most of the day (around mid-80s with mid to high humidity). Went to put flowers in, tailgate started raising, then pop. It kept on going and didn't do it again after that. We both laughed because if it does it again it would be our 4th warranty item, a tech at the dealership backed into it while we were getting it state inspected, and I just ordered a 22" wheel option online just to find out its a LPO which means I can't actually get them since I've already ordered and taken delivery. Guess the tires will be in the garage lonely for a while. Sorry for venting...it's had a rough month for the new vehicle, but yes I have experienced the same issue.