Hello, My problem was : "I have a problem my car doesn't go forward or backward. There is all installed. " I resolved that in wheeldir opposite direction. The powertrain is correctly build. I have also the error no exhaust end node found. My second problem is my car is too heavy, WHY ? When i get down the weight of the nodeWeight of the tire under 7, it bugs. { "nodeWeight": 0.39 }, I resolved this problem too !!! I don't know why now some part of the tire get away, look at the image. Somebody Can see my problem and help me ?