07 denali hesitation

[double e]

On my '07 Denali, at low RPMs or when coasting then accelerating, tranny feels like it slams/jerks in to gear. Almost like when a u-joint was going out a long time ago....anyone had this issue and if so, how was it fixed?

thanks.

 

[CEN2MENTAL95]

how many miles? what color is tranny fluid? is it dirty? any CEL codes?