Lincoln 2011 MKS Owner's Manual page 344

TRANSMISSION CODE DESIGNATIONS
You can find a transmission code on
the Safety Compliance Certification
Label. The following table tells you
which transmission each code
represents.
Description
6-speed automatic transmission (6F50)
6-speed automatic transmission (with
EcoBoost) (6F55)
2011 MKS (mks)
Owners Guide, 1st Printing
USA (fus)
Maintenance and Specifications
Code
J
C
343