Land Rover Repair: Engine Knocking, tappet noise, piston slap

Question
I have a 2003 Land Rover Disco with 54,000 miles.  When the vehicle is idle there is a loud knocking ticking sound.  I took it to the dealership and they said the only way to stop the knocking was to replace the engine because of a slipped sleeve they would be unable to get to.  They said the car ran hot at some point but I have had the car over a year and it has never run hot or had any leaks.  The car runs fine with no loss of power.  Should I just park the car until I can get another engine or should I get a second opinion?

Answer
I would certainly get a second opinion. A slipped liner will typically only make noise when the engine is warm.  It would be quiet at start and, normally, there would be coolant loss and misfires.  

Be aware, if there are only one or two slipped liners, your own block can be economically repaired at a machine shop and re-installed in your car.  The dealers usually don't mention this option as they don't rebuild engines.

This year and model also suffers from piston slap on start-up.  This will go away after a minute or two.  Rocker shaft tappet noise is also quite common.  These are two other possibilities to look into.