Cat D3C dozer transmission problems

our D3c dozer just stopped moving and I am looking for help troubleshooting the problem. We were back filling a power line trench when it quit. I started the dozer and let it warm up like usual and pushed a straight line for about 100 feet. Put it in reverse to turn around no problem. Put it in forward and nothing. Reverse again, moved about 4 feet. Forward again, nothing. Then reverse wouldn't work either. When you put it in either gear you wouldn't feel any movement or hear anything different. We ended up dragging it on a trailer to get it home. Both tracks rolled freely when we dragged it onto the trailer. Checked the oil in the transmission and bevel gear. Both full and looked clean. Checked the transmission filter, clean. Raised both tracks off the ground and tried again. Now you feel the transmission kick it and it tries to move but won't. The dozer info is 1992 cat D3C. Product ID# 4HJ00513. Serial # 7YJ00346. Trans. # 9AE01819. This dozer has a full cab. Any help is greatly appreciated. Thanks.

mfortier have you checked the linkage the tranny cases were prone to wear ive seen 1/4 inch lost movement where the shaft comes out of the case on top left side. I have just unhooked the linkage going to the tranny and worked it by hand to know .

steve loving, thanks for the tip I will check that out this weekend

The first step for troubleshooting should always be to check the filters and screens. Cut open the filters and post pictures of your findings, we may be able to help.

Well I finally got around to actually starting to work on the d3 and found that a u-joint had come apart. Meaning the transmission wasn't connected to the bevel gear so that's why it won't move DUH!! I was expecting a much bigger problem but I got lucky. Thanks for the help! mfortier