Another JD 450c transmission problem

[Crawlinallover]

Hello I'm having issues with a JD 450c dozer not moving after running in 4th gear. I usually never run in 4th so i thought id try it out. After that i went to 3rd and it engaged but did not move so i went to 1st and 2nd then it would not engage or move. so i checked the fluid level and it was a little low added fluid then it moved but it was very sluggish and took a while to engage the gear. now it will not move again.

Changed the fluid and pulled the filter screen on the right side it was not bad but there was what looked to be golden flakes or pieces of clutch material. so I hooked a pressure gauge up and at idle in neutral i only get about 60 psi. If its up to about 1600 rpm and in gear it will rise to about 150 psi but it takes about a minute. I tried tightening the clutch adjuster but no rise or decline in psi. also if I look in the hole i can see the pressure plate spinning but it still spins when the clutch pedal is engaged.

Another thing is sometimes when i would shift to third gear it would not move and grind when shifting out even with HLR lever in neutral. Also it was starting to make a screeching sound when going into high and it always whined a little in reverse. I am thinking maybe there is an internal leak or some debris in a valve somewhere but as of now i'm stuck any ideas where to start would be great.

Just thought of this should there be and air bubbles in the oil when it's running? I can see the oil moving when the plug is off above the pressure test port it has some bubbles in it and is milky green even after changing it twice.