Hi All I have a case 450B crawler and could do with a bit of help. i recently changed the trans oil as it was milky and horrible looking no metal though. i didn't touch the filters a i intended to run it for a few hours and drain it again so as to flush the system and change the filter and clean the screen then. i drained it and filled it back up with 15w40 diesel engine oil - that's what Dr google recommended and i don't have a workshop manual yet. i ran it for a few hours no problems ripping up a patch of dirt where i intend to put my orchard. then drove over and started to rip out a few small stumps - black wattle so pretty shallow rooted and it wasn't working hard at this point. it pulled the first two out with no issues and as i was reversing back to get a third the transmission pressure gauge dropped to nothing and i lost all drive suddenly. now since i got the machine the gauge (three colour not psi) has always read low pressure, in the high side of yellow, but i have been told these type of gauges are often inaccurate and it drove really well so never bothered about it. it has always, right up to the point it stopped been very positive in the drive and turned well and shift high to low nice and smooth. i have removed the plates and can find no leaks also the drive shaft is still turning and there was no abnormal noise when it stopped. converter temp was still in the green also. my thoughts are possibly an issue with the pressure relief - broken spring or something of the like? because i don't have a workshop manual i'm not sure where the pressure relief is located so if anyone has any insight that would be very much appreciated or if anyone has had a similar issue or more experience with these that might be able to point me in the direction of where to start looking? thanks in advance Oly
I change the filter and clean any screens first
oly89; here is a link to a 450, not the B series service manual. It should help you some I hope. Sorry I do not have a B series link. https://www.minnpar.com/manuals4.as...e=CASE CRAWLER DOZER MANUALS&SSFName=Case 450
Welcome to HEF @oly89 ! If the driveshaft is turning that is a good sign. Just a thought, make sure your mechanical 2speed has not been bumped into neutral..... The transmission pressure reliefs are located in the convertor housing, but I don't think that is your problem.
cheers for the replies, and thanks for the manual. most helpful
Check your trans pump up on the engine under the alt. on right side of engine, make sure you are getting oil flow from it.