Im Looking at purchasing a discovery II and have some general questions about wear. how many miles can one expect to get out of the drivetrain and what are any major common issues

 

What are you planning to use the truck for?
If it is a daily driver and weekend off roader, the diffs, t/case and tranny hold up well. If you plan on lots of hard core off roading, you may want to install some lockers to get the heavier cases needed for that sort of abuse.
Mike