The front axle itself does not need to be removed.
you dont have to but it makes it a lot easier.
you need to remove the transmission then unbolt the clutch from the flywheel.
Remove transmission oil pan for filter access
drain the fluid out of the transmission pan, unbolt the pan, remove the filter and replace
Remove the tranny oil pan and you'll see it.
Transmission filters are INSIDE the transmission. You need to remove the transmission oil pan. When you replace the filter, plan on replacing the pan gasket as well.
There are freeze plugs in the side of the block, the heads and in the back of the block between the motor and transmission. If it is one of the ones on the back of the block, either the engine or transmission has to be removed to get to them.
It is illegal to remove a converter from any vehicle without replacing it with a new one.
Remove the driveshafts, unbolt the transfer case, unbolt the transmission from the bell housing. Disconnect any sensors. If it's an automatic, Unbolt the torque converter.
remove the pan on the bottm side of the transmission and you will also exspose the filter and change it at the same time
u need to check your exhaust system i have never yet seen any diesel that has a catalytic converter installed
You will need to remove the transmission to replace the clutch slave.