As on most I'm sure the transfer box leaks quite a bit of oil. Awhile ago I thought I'd replace the 'gasket' only to find there isn't a gasket. So I used LR's own sealant. I drained the box left it to drain overnight with the cover off and hopefully thoroughly degreased the edges before applying the sealant. It didn't last for long before it started leaking again.
Is there a gasket equivalent instead of the sealant? With the new MOT rules they don't like old dripping everywhere.