Time to get your (or someone else's) hands dirty. Start by pulling the right
front hub apart and looking for damaged parts, broken CV or similar.  Check
the front prop shaft U-joints (if it has any). If nothing is obvious, move
further inwards. Check the front swivel joints are not worn out.

Stewart DIBBS

The noise you can hear is the 4wd trying to engage ( assuming its from the front )

Check the vacuum lines to the 4wd solenoids and to the actuator on the front diff.

The 4wd engages everytime you turn off the engine , when you start the vehicle the vacuum pulls the actuator out of 4wd ( as long as the transfer stick is in 2wd ) The noise you can hear is the plunger trying to lock the front diff into 4wd.

Hopefully you can relate to what im saying.

Jeff
 Hello to all:

 I have a 1986 Montero 2500TDi, with a 4D56 Engine recently overhauled, and
 my problem is with the transmission:

 Whenerver I put in reverse and try to go forward, a few meters away a
 sound like a cog wheel scratching another one starts (it's louder near the
 right front wheel); it stops immediately when I hit the brakes to a full
 stop (and a clock! is heard right before the full stop) and then connect
 the 4x4 in 4L, drive a few meters away and when I disconnect it the sound
 won't present again.

 Also, when engaged in 4L and try to turn left, there's an ifernal sound,
 like all the transmission tree is going to blow, something like a repeated
 banging sound.

 I don't exaclty know where the problem is, but any help will be
 appreciated.

 Thanks

 Tito

When were the auto-hubs last serviced? Since you are able to go
forward a short distance with no noise, it sounds like one of the hubs
is trying to lock up. The auto hubs need oil, not grease.

Check out    www.4x4wire.com
There is a good number of Mitsubishi 4wd owners there.