whats wrong with my LC 80

Noise in the driveline travels, if it were me I would be removing the rear tailshaft and taking a very close look/feel of the rear diff, rear bearing and centre diff. Grey matter in the oils would be a red flag.

Probably not the same for you but I had a rattle that drove me nuts,turned out to be the wire from my GPS vibrating against the centre console I kid you not,so easy yet so hard to trace,hopefully something similar ?
regards,
Dave

We just replaced the rear tailshaft. The old one was making noises and on inspection it was bent.

Steve, I had a similar thing on a 75 series (noise would come and go) and it turned out that one of the springs that hold the rear handbrake shoe in place had popped off (when you see it you'll understand how it happened - bit hard to explain in words). Hence the spring and a couple of other little bits of metal would occasionally get "picked up" and dragged around inside the housing.

Jack each side of the rear up and spin the wheel and see if it makes a noise or just pull each rear wheel off and disc to check the handbrake shoes (this is assuming the 80 rears are the same setup as the 75's ???).

Had me stuffed for ages too. I just disconnected that side handbrake as the handbrake was useless anyway. Wouldn't cost that much to fix anyhow.

Hope this is it mate.

Steve, I had a similar thing on a 75 series (noise would come and go) and it turned out that one of the springs that hold the rear handbrake shoe in place had popped off (when you see it you'll understand how it happened - bit hard to explain in words). Hence the spring and a couple of other little bits of metal would occasionally get "picked up" and dragged around inside the housing.

Jack each side of the rear up and spin the wheel and see if it makes a noise or just pull each rear wheel off and disc to check the handbrake shoes (this is assuming the 80 rears are the same setup as the 75's ???).

Had me stuffed for ages too. I just disconnected that side handbrake as the handbrake was useless anyway. Wouldn't cost that much to fix anyhow.

Hope this is it mate.

Hello Steve,
When I had my gxl 80series ,I had a funny noise comming from it as well which seemed to be a transmission issue. The noise would only last a few seconds and then go away.
Took the 80 to several transmission places and got a lot of headscratching and no answers.
As I was going on a holiday towing a caravan I elected to have the transmission removed and rebuilt on the advice of a transmission expert (auto) to see if any problems were evident, cost about $2500 which included a new torque converter.
Imagine how annoyed I was when the noise came back two days later and the advice given was" just drive it till it breaks then we can fix whatever it is".
Anyway comming into Carnarvon in WA it was terrible so took it to a somewhat backyardish mechanic whom not only correctly diagnosed the problem but fixed it in 2 hours and only charged me $120. You can imagine what I was thinking of the so called transmission experts in Bunbury where I live.
Anyway it turned out that the front cv shafts were running dry and needed greasing which is what was causing the noises. (noise travelled up the tailshaft into the tranny). There is a bolt on either side of the front axle housing(on top) that a grease nipple should be screwed into and a quantity of grease pumped in occasionally. This noise manifests itself worse after a long run due to heat and lack of grease.
After three years the noise never returned. I know you said your noise was from the rear but as I found the noises travell in the driveline.
Could be a cheap fix for you.
Regards Alan.