transmission issue on 2007 Buick LaCrosse

it is periodic but sometimes the transmission will have a long shift from 1st to second and second to third then sometimes when pulling out from a stop it acts like its not in gear and doesn't want to go push on the gas and it will engage but is not a good sound when it does it and sometimes instead of a long shift it is a short rough clunking shift and sometimes it is perfect and never a check engine light ever when any of this happens.

Asked by for the 2007 Buick LaCrosse
1 answer
ck fluid level and condition. poss a trans service would help if it hasn't been done