I have a mid-2015 Yukon Denali which is an early production truck for the 8-speed transmission. Have had problems with the transmission since day 1 - whining noise, bad shifts at low accelerator input, bad downshifts, etc... Terrible performance.
I have also had front suspenion issues that have required numerous parts to be replaced some 3 or 4 times already by the dealer while I was under warranty. They have replaced struts 3x, bushings 2x, re-torqued everything several times, found bad strut tower brackets, replaced the steering column 2x, etc...
Not to mention that my radio does all sorts of strange things like blacks out, sometimes get frozen on a incoming call, etc...
I recently discovered Max @ Xineering.com. He makes a plug-n-play resistor kit to delete either the front Z95 magnetic ride system or to delete the front magnaride + the rear air suspension.
Am planning to order his kit this week and install normal mechanical coil over front suspenion with normal shocks on the rear.
I am done with the issues with this suspension on my truck. This is by far the worst GM truck I have ever had. I will likely not by GM any more. I am now out of warranty with 43k miles and I am told too bad, you need to pay for repairs. GM offered me $6,500 as a settlement but it hardly compares to having a $74k truck that works the way it should....