2015 silverado transmission shimmies on the up shift

[Mike Donahue]

my truck shimmies when the transmission is up shifting thru the gears. first I thought it was the road, but after many vibrates I've come to the conclusions that its the transmission. also the clunking I hear sounds like a U-joint going out. has anyone experienced these same issues. thanks for any help.

[ejdziurka]

I get the clunking noise on downshifts... Took into the dealer, they provided a TSB that said the dealer should not spend any time diagnosing any drive line clunk.  Basically it's all the lash in the parts coming together to make the clunk.  Normal operation and ill effect on longevity.