recently the rear diff in my 1998 land rover freelander has gone (makes a horrible clicking sound around corners). The car has been a constant pain and i was wondering what is actually the cause of the noise (possibly worn teeth of diff?) and if it is possible to remove the rear diff from the car. This looks like a fairly simple process after a quick look, and wear and tear is a small concern as im looking at flogging it off as soon as i can. The car is permanent 4wd and has no middle diff between the front and rear, instead it uses a viscous coupling. thanks!
As far as I remember, rear diffs and the viscous centre diff are known problem areas on the Freelander.
If you remove the rear diff, the viscous centre diff will attempt to compensate for what it believes is a permanent no-grip condition at the rear wheels. Chances are that you'll blow up the centre diff in very short order if you do that. So no, I wouldn't recommend just removing the rear diff.
BTW, a horrible clicking noise from the back can be something as simple as a bearing on the way out. I'd have someone who's familiar with these vehicles take a look. A quick Google found a copy of a warranty bulletin detailing a bearing issue on early Freelanders.
Yes - you can make the freelander into a front wheel drive vehicle.
You will need to remove the IRD (essentially the center transfer case) and replace it with the same unit from a 2WD freelander. The rear drive shaft and diff should be removed, and you may need to disable some sensors depending on your locale. The rear axle housing can stay, but if you get the rear axle from a 2WD then it'll be smaller and lighter. If you keep the old one, fashion some kind of sealed cover plate for where the diff was mounted, and bolt it up.
This is a common workaround for those whose IRDs have imploded, generally due to mismatched wheel speeds.
Since your fault was something else, be aware that the IRD is nothing more than two big paddle wheels running inside a bath of special oil. This oil's resistance changes if its being churned. whereas when both paddles are moving at the same speed the oil remains a liquid. So, if you have disparate wheel speeds then the oil is "locking up" and will eventually lose the ability to return to liquid state. This leaves you with a locked transmission and you'll get windup, and eventually the weakest link will fail.
Upshot - check your tyre/tire pressures fortnightly on a freelander, with a decent gauge, and keep them at the right pressures for your tyres/region/weather always.