F*cked diff

Hi all. Today my rear diff packed in whilst off roading. Somehow a hole has been blown out the back of the casing (a couple of mm in size). Does anyone know what could have caused this? The propshaft turns into the diff, but nothing turns out of the diff. I guess I need a new rear axel? WOuld a salisbury axel fit? Its a 88 series 3 (1984). Thanks.

Edit. The hole has definitely come from the inside of the diff because the metal has been pushed out. I am 100% it is not a puncture because I had a diff guard fitted and it has no marks.

a Salisbury isn't a direct fit but they can be made to fit, it sounds like one of the pins that the planet gears runs on has snapped and the diff has eaten its self, the easiest fix would be a new diff(about £40 second hand) and weld on a new diff pan they are available from paddocks i think

Thanks for the quick reply. Thats a slight relief. Pain in the ass though lol!

yeah its a pain but at least its not worse, how is your welding?

I've never welded, but I have a couple of mates who are average at it. Would I need a new diff unit or just the internals? And I guess the pan just welds to the back of the diff? Thanks

the pan welds onto the axle case, i would be tempted to grind off any protruding bits of diffpan and weld a plate over the top of the hole, it would make it stronger, it would be easier to get the entire diff unit in the casing as its alot easier to change

ok mate. Thanks for the advice. I'll start searching for the bits I need then.