Our best trolling technique has been pulling crank baits like #5 & #7 jointed shad raps, #11 floating rapalas or #7 or #8 deep diving shad raps on lead core line.
Lead core does a great job of putting your baits right where you want them. With lead core line, regardless of how deep you lure dives, you can control just how far off the bottom that bait runs. Some days the fish like the bait within six inches of the bottom and on other days they will hit baits run two or three feet off the bottom.
With lead core, you can control exactly where in the water colum your bait is.
Typically, we have been finding our fish in about 20' of water. Early in the morning, they may be up in 16' of water and as the day wears on, they like to slide out to 22 feet of water.
Changing lure colors when the bite slows down can also be a very effective way to put a few more fish in the boat.