Yo vstevens. Finally tracked down my bro who is presently floating around our Catlins area down south. (Lovely, wild. inhospitable area)
His Disco is a '94 which he rates as one of the best (for whatever reason)
They all are rather thirsty.
Camshaft and tappets tend to wear, usually need doing by 130,000kms. If the cam is bad;y worn it could need replacement.
The auto the use is a ZF and is a beauty. 40,000kms service on auto.
The transfer case uses EP90, NOT ATF. If ATF has been used they will whine.
If it is a manual it will be a 380 gearbox, which is "a prick to rebuild".
Early '89-90 were a 3.5 carbed, then went to injected for a couple of years.
Around late '92 they went to a 3.9
'98 they changed the injector system, although there was nothing wrong with the previous model.
The alarm that was fitted came with two different frequencies. The 315MgHz was bad because a lot of garage door openers were around that and the alarm gave no end of trouble because of it. The other was 433MgHz which is a much better frequency.
He has had his for years and has been anvil reliable.