I posted earlier I was considering upgrading gears because my YJ was a dog on hills. Strange thing happened on the way to work this am. While in 2nd gear my jeep bogged down for a split second..then all of a sudden it took off..like I had a extra power boost. Every mountain I went over and incline... I cruised up with at ease in 4th gear. It was like something released. Has anyone ever experienced this?? What was causing it to run like crap before this? Could there have been a vapor lock or something?? I'm puzzled! I love the way it is running now, and don't need a gear upgrade.