Hyundai Repair: 2006 Sonata LX V6 Question., oil leaks, transmission assembly

Question
How long does it take to replace the timing chain on this vehicle? Is it a hard job? What thing I should be watching out for after it has been fixed? Will it cause other parts within the engine to go bad too?

My car is currently in the dealer right now due to the rattling noise that coming from the engine compartment whiles it only 3000 miles on it. At first they checked it and said that it just a normal engine noise but after a couple weeks later it got worse. After a couple times going back and forth showing them, they said that theres something wrong with the timing chain and they are trying to fix it.

Please, help.  Thanks.  

Answer
I'd count on an entire day to two days of work.  How long your car is in the shop will depend on whether the dealer has a technician that can dedicate his time to your car only.  We've done a few of these in the shop where I'm employed, but I've not had to do any yet.  The issue is that the ratchet in the timing chain tensioner doesn't work properly.  The dealer will be installing new (revised) tensioners to prevent the accumulation of slack in the chains after the vehicle sits without being driven.  

Typically, the engine and transmission assembly is lowered out of the car and work is done with everything out of the car.  I've seen several variations on what to take apart to remove the timing cover, some better than others.  I wouldn't say the job is hard, but it is somewhat labor intensive.  

Neither the problem nor the repair should cause any sort of consequential damage.  After the repairs, keep your eyes open for any oil leaks.  Sometimes not everything seals properly.