[confuseee]

i have a 2000 gmc sierra 1500 z1 5.3 v8 :?: i just had a new transmission and torque converter installed like 6,000 miles ago and for some reason now when it shifts into overdrive i can't remember if it did it before or after i got this installed but when it shifts into overdrive and i gas it at low rmps around 1500-1800 without it downshifting my whole truck will shake and make a grinding noise i took it back to the transmission shop and the torque converter doesnt seem to have a problem on the computer when it was hooked up and took for a test drive any ideas before i take it to stealership :?: :? :roll: :|

 

[Silvery13]

Welcome Aboard!

Is the shop you went to the same shop that installed the new trans and TC? And they haven't a clue what the issue might be?