I have a 98 Jeep Wranger with 128,000 miles. Purhased Jeep about a month ago. While driving in 4th gear driving about 45 mph my rpms will go from about 1800 to 3000 and then drop back to normal. Not sure if this is a clutch issue or transmission. I've started to see this happen in 2nd gear as well when I heaily acceplerate. Thanks for your help!