Noticing a slight hesitation/jerk when trying to.

Noticing a slight hesitation/jerk when trying to maintain speed going up slight hills. To maintain my speed I softly accelerate and can feel it in the pedal. Once the road way levels out it seems to run fine. Don't have extra money right now to take to the shop so I was going to attempt diagnosing problem myself. Any thoughts on where to start? Do not have any leaks. Also, what are the chances it could be transmission related. I know these trucks in the past have had issues. Any comments would greatly be appreciated. Thanks KH