Thanks in advance for all your input. I bought a 2006 Wrangler about two months back. It has recently developed a swing in the rpms when I am traveling 60 - 65 mph. The tach will drop 400 rpms when I am traveling in overdrive. When in high gear out of overdrive, the tach drops about 200 rpms. The rpm drop occurs and then goes right back to when it was previously running. It is not a one time occurrence rather happens repeatedly. I do not think the transmission is shifting down when this happens. This is happening when I am traveling in non-hilly areas. It is not doing it consistently. It may be a non-event for entire trips but then shows back up. One other note, it has died on me twice while traveling. The first time it started right back up. The second time it took several tries and 20 minutes before cranking. As I was trying to start it, the engine would fire but would not pick up and run. Thanks again for your troubleshooting input.