I Have an 87 wrangler with a 400 small block Chevy motor. I'm using it as a mud jeep, but I took it offroad last week and discovered that I have a few problems, my four wheel drive works on dry land and continues working in the mud hole, but when I stop and shift into reverse the front tires won't start pulling again. I don't know what would cause this. I also need a new clutch and bell housing but the jeep doesn't have the factory motor or tranny so I don't know how to find the clutch or bell housing I need. Any help would be much appreciated.