What causes no movement in any gear in a deere 6300 tractor?

hi ebnel, thanks for responding, i have worked with you several months ago on this same tractor and am pleased with your help,,,, now , i will refresh on what we did last time, this machine had a lube warning lite on and we tested pressures and found low lube pressure but normal clutch pressure and decided to run it as it was at that time, but now we have lost all clutch and lube pressure, i checked to see if the three point hitch and remote ports had pressure and they work fine, do all the hydraulics use the same sump screen

thank you ebnel, you are very thorough and i appreciate that, get back to me when you can,,, thanks again

thanks ebnel, i will try that and get back to you,

hello ebnel, i removed the filter and ran the engine as you recomended, there is no fluid coming out at all,, the owner of the tractor claims he spoke to the former owner and this person said he had the identical problem and took it to the dealer and they replaced a electrical relay at the fusebox and solved the problem, also claims this had happened again a few times,, i see there are some sensors and switches in the valvebody by the filter but none appear to control anything,, this makes no scents to me, broken relief valve spring maybe or weak pump lost its prime because it worked fine when he parked it ??

ok ebnel, will check this out, thanks

thanks ebnel, i drained the fluid and next checked that sump screen in your illustration and it was indeed plugged, the fluid that first came out was very moisture laden and screen appeared full of buffalo snott,,,,, thanks again,