From Ford Tech Service bulletin Sep/Oct 2009:
Approval to Service ALL 5R110 Automatic Transmissions with MERCON® LV
Beginning immediately ALL (2003 to 2010 MY) 5R110 automatic transmissions can be serviced with MERCON® LV automatic transmission fluid in place of MERCON® SP.
Initially only the 2009/10MY 5R110 automatic transmissions were filled and serviced with MERCON® LV. In an effort to reduce complexity, Ford Motor Company is allowing all previous model year 5R110 automatic transmissions to be serviced with MERCON® LV automatic transmission fluid. This pertains to top off as well as fluid replacement. Mixing of MERCON® LV and MERCON® SP in the 5R110 transmission is acceptable. Extensive testing has been performed to insure there are no functional or durability concerns with the use of MERCON® LV in the 5R110 automatic transmission.
Vehicles affected are F-Series Super Duty trucks (including chassis cab, motorhome, LCF).
Motorcraft MERCON® LV is now available in three sizes:
Part Number: XT-10-QLVC - 1 quart
Part Number: XT-10-DLV - 55 gallon drum
Part Number: XT-10-BLV - Bulk
Further information can be found in the Workshop Manual, Section 307-1, Automatic Transmission
Mercon LV vs SP - Diesel Forum - TheDieselStop.com
The link in this post is broken. I'm still looking for the exact number.