I went to advanced auto for an oil filter and oil for my '06 F150 4.6L STX 4WD. They wanted to know if it was a romeo or Windsor. I couldn't answer them. I found out that you can use the VIN number. What number or letter do you use for the engine place of manufacture?

Thanks.

 

Doesn't matter - the oil is 5w20 Motorcraft semi-synthetic and the filter is a Motorcraft FL-820S for all Triton V-8's. Both available at Walmart.

FYI, 8th character of the VIN indicates engine. A "W" is Romeo and a "6" is Windsor for the 4.6's.

 

Thank you GLC.