I removed my front drive shaft on my 99 to be rebuilt by great basin rover. The forum was a wealth of info about the front driveshaft!

I was looking at the front diff and it appears to be covered in oil - is this a differential pinion seal leak? or something else?

Reading the manual - it sounds like i just undo the bolt and everything comes apart? Goes back together in reverse? is there more to it?

Do i need to drain the diff oil first, or can i just top off?

Lastly - is this the right part? FTC5258G
i am having a terrible time figuring out if i have found the right part online.

 

The most common leaks are the diff seals and half shaft hub end seals. If the oil is around the diff it's normally the diff pinion seal. You'll need to ensure you torque the flange plate nut up correctly afterwards so check your RAVE manual. In theory you should use a new nut and felt sealing washer but no-one ever does.

If it's a D2 it looks right, see below:

Discovery 2 Differential - Front at www.rimmerbros.co.uk

Even if it's a D1 they appear to be the same. Don't worry too much about the suffix letter as it only denotes the source, i.e. genuine LR, oem or aftermarket.

Corteco are the original LR suppliers of these seals.

 

check the bolts around the carrier. mine was leaking not long ago and 4 or 5 nuts were loose. i tightened em all up and leak be gone! yay! But, if you 're gonna reseal the housing, you have to pull the shafts out and yes, you should drain it too. while they are out, good time to replace those seals as well. there's no gasket for the ring & pinion carrier, just rtv, so be sure to clean it real good! a job you don't want to do twice! good luck!

 

Yes, FTC5258 is the correct part (highlighted in red). See schematic below.