I recently bought a 91 YJ with a 4 cyl and 5 spd. The guy I bought it from said he just had a shop replace the clutch plate, pressure plate, and both master and slave cylinder. He had only driven it a couple of times and the clutch was slipping again. I bought it anyway. I pulled all the parts to inspect them and all seemed ok except the flywheel has a little ware and had a glaze. I had a machine shop true and resurface the flywheel. Put it all back together and it felt like new. I pulled strong and hard, no slipping at all. Heres the hairy but..... after a few rides in it all of a sudden I noticed a little slipping, within a mile it went from like new to not even trying to nudge the vehicle. If anybody has an idea what the problem could be...Please Please let me know. I realy want to move on to more fun stuff with the Jeep.