Ford Freestar 2006 Owner's Manual page 309

The Vehicle Identification Number (VIN) contains the following
information:
1. World manufacturer identifier
2. Brake type and Gross Vehicle
Weight Rating (GVWR)
3. Vehicle line, series, body type
4. Engine type
5. Check digit
6. Model year
7. Assembly plant
8. Production sequence number
TRANSMISSION/TRANSAXLE CODE DESIGNATIONS
You can find a
transmission/transaxle code on the
Safety Compliance Certification
Label . The following table tells you
which transmission or transaxle
each code represents.
Description
Four-speed automatic (4F50N)
Maintenance and Specifications
Code
N
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