4.3L VIN code

[pcrow]

My 2003 Silverado reg/short/2wd has an engine code (8th digit) of "X". The manual, and most internet sites list the 4.3 as having a VIN code of "V". I discovered this when purchasing my first oil filter for the truck. The "X" one is twice the size. I can find no listing for a 2003 with "X" engine. What gives?

[robsawatsky]

I found a listing for an "X" engine VIN code relating to an LF6 4.3.

 

Does your RPO tag in the glovebox show an LF6?

[pcrow]

This is where it gets strange...the glove box lists LU3, which is a 4.3L. Other research has shown the LU3 as VIN code "V", as the owner's manual states. I also realized that the oil filter for the "X" LF6 is the same as 98 p/u that I gave to my son. I am begining to think that this is a very early 2003, and it may have some '02 leftovers!

[Mr Mojo]

my '91 had a VIN code of Z if I remember right