SG_M3

I'll try to make a long story shore, but this issue is driving me insane.

2011 GL450
89k miles

Took it in and had the motor mounts, trans mount, new shocks/struts installed on all 4 corners, and new intake runner flap. When it came back, after about 15 minutes of driving, it started to have a vibration that started just as the trans shifted, lasting between 35-45 mph. Then it goes away.

We've had the driveshaft on and off, checked everything multiple times...but cannot fix the issue.

I'm getting feedback now that the shop believes the transmission is going out. Really weird that this all happened after replacing the above items. Anyone have any ideas? Going to get a second opinion by the dealer before evaluating my options on transmissions.

gl450x164

Center support bearing

alx

begin by rotating tires (trust me). if shudder still present - check center support bearing. check rubber cake on rear driveshaft. check u-joints. if all good - check rear lower control arm bushings. check rear sway bar bushings.

if all of the above is ok - have the tcu adaptations reset by the dealer.

if still presented - have dealer troubleshoot 722.9 by means of star/ das - observe shifting pressures. if something is going on in there a competent tech can detect it.

if still issues - drop transmission pan and check fluid and deposits on bottom of pan. replace fluid and filter anyway.

let us know how it turns out.

SG_M3

We replaced the tires, all 4 brand new and the issue continued.

I will double check and pursue the other items.