Circle drive

View attachment 177136 View attachment 177136 hello . I was operating my caterpillar 140G and the circle stopped turning for me . I have ordered a pinion however I may need some advice before I put the new one on . I was reading a earlier post on this forum regarding the circle drive and the shaft / shims etc all play a part . If I put a new pinion on i am nervous I may break the shaft . I will try post a picture of the pinion . Any advice for this subject would be greatly...

Circle drive

Circle drive