I just purchased a used 450 case and had to rebuild every cylinder on the hydraulics. after that the exhaust was next, it seemed to work great till i backed it into my shop. The next morning when I got to the office I went to move the machine out and noticed right under the seat area and one or two more areas up towards the front there was hydraulic oil. The back spot was quit large like the size of a basket ball then about midway to the front was a spot about half that size and up front was another spot about half again. Im new at this dozer stuff so does anyone have any ideas what could be causing this issue, It was dry when i went to get the machine when the guy loaded it we saw a small amount leaking but we could not see from where. then we used it at my office and it was ok, then i used it again and backed it in and then is when I really noticed this. Help is neeeded. Thanks.
I would put it up on 8" blocking and drop the front and rear belly pans and see what you have the first chance you get. This gets them cleaned out leaves/trash/dirt and lets you get a good look. Could be a gasket/line/seal/clamp. Sometimes you can see enough with the floorboard/seat/engine side panels off also. You will need a safety bar for your loader if you don't have one when working in the engine area to keep you safe when it's raised and service/repair work being done. I can think of many areas that could be leaking, you have to look for us and tell what you see or take some pic's so we can see and give our thoughts.
I agree with sheepfoot, get the unit up on blocking, get the pans off, mine were so full of junk it filled a loader bucket on a farm tractor as cleaned out. Without seeig what you are dealing with it is all guesswork.
Those belly pans are heavy. Transmission jack is useful in safely removing & replacing. I had to replace some of the hoses under there a few times. Not a fun place to work.
There is an o ring and seal on the shift spool,down low between your knees.Common leak,and easy fix!