Rear Diff Lock for SAND??

[wregan]

I'm about to purchase an '09 RR Sport. I spend a lot of time on weekends on the beach fishing. A lot of flat Ocean front, can be soft or wet sand and then some easy rocky/sand on other side of Montauk. Will i need the locking rear diff for this type of driving or should i save the loot? also, can i add a locking differential after purchase or is this better left to the factory. Thanks -Will

 

[joey]

can't add it after the fact... I don't think you will need it for sand but it will never hurt to have it just in case.