17 Yukon Denali weird Vibration

[Cuzican]

My wife's 17 Yukon Denali 2wd has developed a weird vibration, I did a quick search, but didn't see anything that sounded the same. When accelerating it randomly vibrates in what feels like the rear end, the best description of the vibration is it feels/sounds like you are running over the drunk bumps on the outside shoulder of the road for about 4 or 5 bumps then stops and a few minutes later it'll do it again. The only common thing I have noticed with my few minutes in it, is that as far as I have noticed, is that it seems to only happen under acceleration. My initial reaction was to think the magnetic ride, but now I'm wondering if possibly something else. Suspension is all stock, I did change to OEM reproduction 22's on it with Michelin tires. Wheels have been on it for a couple of months with no problems, so I don't believe they are the problem, but I plan on putting the factory wheels/tires back on tonight when I get off work and seeing what happens. I plan on digging further into it tonight, but was just curious if anyone else had had this problem or one similar.

 

[Tahoe14]

If the factory tires don't change it then probably the TSB for the tranny. The Dealer should be familiar with the issue. They will need to re-program the tranny and do a fluid change. Next if no improvement would be to replace the torque converter.

 

[Cuzican]

Spoke to the dealership and made an appointment, the advisor said the same thing, so guess this thread is in the wrong section now. Guess we'll see what happens after they look at it.

 

[bmwman3241]

What did the dealer say?
I am having a similar vibration on my 16 Yukon XL Denali 4WD, and it feels exactly how you explained..running over the lane bumps for a few seconds.

I have noticed as well thats its only under acceleration, and 70% of the time between 40-55mph, and happens a lot rougher when going uphill.

Any idea what it could be?

 

[CMoore711]

Definitely sounds like the torque converter shudder TSB. My '15 Denali XL had a similar symptom, as well as hard shift into Drive and Reverse from park when cold started. Dealership performed the TSB; reprogrammed the TCM, did a trans flush with new fluid and haven't experienced the vibration since. It solved the problem and it's been 15K miles since.

 

[Cuzican]

They said torque converter shutter, it is in the shop today, I should pick it up this evening. From what he said they are gonna service the transmission and reprogram the TCM.

 

[drmn16]

Thanks for posting this issue and the answers... I bought a 2015 Yukon Denali a month ago and notice this vibration at highway speeds. I recently went to 22" OE wheels and new tires and the highway vibration is still happening. Now I know what to talk to the dealership about.

 

[Cuzican]

So far, after one night of driving, the problem seems to be fixed. Thanks to all that helped.