99 GMS Sierra trans problem?

My 99 GMS Sierra - 2WD has 95K miles and has been great. I just made my final payment so I know that means trouble! It is well maintained as far as oil changes, transmission fluid changes, tires, etc. Recently I have noticed an intermittent problem that concerns me. After driving for 30 miles or so on the highway at 70 - 75 MPH, I have notices what seems to be surging as I get off the interstate onto the ramp. It seems like it is trying to jump into passing gear but doesn't and I am not giving it enough gas to jump into passing gear. This evening, I noticed it hesitating and kind of surging as I accelerated from about 30 to 30 and then onto the highway. Any ideas. I do not notice any change in RPMs on the tach. I would have the vacuum checked I would definately rule out a drivability problem BEFORE attempting any transmission repairs. Many times drivability problems are mistaken for transmission problems. It is VERY important that the engine is in top working order for the transmission to operate properly.


transman