I have a bass pro pro qualifier bait cast reel that has been malfunctioning. It is about 2 years old. I had it out recently, and I had a lure stuck, so I gave it a jerk with the rod. When I did this, line came off the spool giving me a large over run. This has happened a few times. The drag is tightened and the spool tension is set properly, and I wasn't touching the thumb bar at all. Any ideas why it would do this? What do you think I should do?

wait till the spring sale and buy another one for about $40 or so or send it to DVT and have him take a look.  other than that, i don't know.  My few forays into reel maintenance didn't end well  so i just send them to DVT.

If the handle did not spin backwards when this happened, the only way that I know of that would be possible for the spool to spin fast enough to create a large backlash is if the spool pin came disengaged from the pinion gear.   If this is what happened I would look at weak clutch/yoke springs.

Off the top of my head I can't envision anything that would cause what you describe. The pinion slipping would make a ratcheting noise. Other than that the drag shield slip. I'll look into it if you want.

there are so many good youtube videos on opening reels, even the PQ. if ur going to be fishing alot it's inevitable ur going to have to work on ur own reels.  it's actually easy even if ur not mechanically inclined.  i was dreading it the first time but decided to only clean the gears and grease the drag. i opened/cleaned 3 reels before I started on the bearings.  by that point i was confident i could get them back together w/o problems