Transferring Ultegra SL Crankset

snharding
snharding Posts: 23
edited May 2011 in Road buying advice
I have a Trek Madone 5.2 with a 53x39 Double Ultegra SL crankset, which I would like to replace with an Ultegra SL Triple. I realise this will mean changing shifters etc. What I would like to know is can I transfer the Ultegra SL 53x39 on to my Trek 1.5D. The 1.5 already has an inferior 53x39 set up, so I won't need to change the shifers presumably?