Welcome. You can change to 4.88's, it will help, but is not a cure all. Though you might want to consider upgrading the rear dana 35 to a stronger axle before you spend money on it. Ford 8.8 make a nice swap. Gear swaps will vary in cost but figure 1000-1500 depending on your location. junkyard 8.8 200 bucks and another few hundred in parts to make it fit on the YJ.