Caradco Truth Crank Window Gear Replacement

Thanks for posting. I am afraid these individual gears are not really meant to be replaced. When the gears break down, the entire operator should be replaced. Fortunately we likely can help, but I need to see the entire assembly, including the link arm(s) that jut out the back of the operator body. A bird's eye view, either with the operator removed from the window or at least with the window open, will help us narrow down what you need. 

These photos are perfect, thank you! Based on what I see here, my top recommendation is the 39-156 Caradco window operator. We also sell the 39-155 for the opposite side. Your next step should be to review our dimensions to verify that the arms are the same size; based on the codes printed on each arm I think they should be, but it never hurts to double check just to be 100% sure.

Dimensions for 39-156