LT 77 gearbox fault

hi I have a 1986 2.5 defender, I bought it knowing that the reverse gear jumped out, you need to hold it in all the time or it just jumps out, however this is not the reason for the post, recently an odd noise has appeared from the front end,I can't seem to locate the exact area but imaging the noise an old S3 makes in low range and multiply it some!!!
could it be that the gearbox has finally decided to give up the ghost? or could it be the front axle? ( this has had water in it following my playing around in the floods)!

also, I'm assuming that the LT77 is the same LT77 as in the older Discos? that may seem a silly question but did Landrover really use an old type gearbox on their (at the time) new state of the art Discovery!?!

cheers guys
Russ

the early lt77s did suffer poor reverse , idler gear didnt fully engage so teeth wore and once worn jumped out ,reverse switch been wound into far can cause similar ,disco box is similar ,but longer in the bell housing and has different gear lever assembly ,but both boxes were improved over time and apart from mainshaft spline wear caused by the t/box input gear were reasonably good boxes ,the later r380 is only an improved lt77 ,not quite as odd as a 30s design gear box lasting till the mid 80s in the series

Thanks for the reply, ive managed to locate another gearbox now as the old one finally gave up the ghost! going in this weekend

dont scrap old box ,they are getting very hard to find for rebuilding ,scrapping defender boxes will make it harder fot those wanting one in the future ,sell it or give it to a lr box rebuilder