The teeth are eaten up. It's not clear in this picture but they are. We have both parts, I just didn't take a picture of the other part. Pictures 1 & 2 are the front and back of the old part that the teeth are eaten up on. Picture 3 is splined piece that it fits into which goes to the actual shifter on the transmission. The last two pictures are of the part that is wrong. I am wondering if it is an improved version of it and we need to change the little arm part also.