Why different filters for C1500 5.7L & K1500 5.7L?

[threeed1]

I have a 1997 Chevy Z71 I bought used and the previous owner changed out the engine (not sure but think it came out of a Chevy van?).
The engine is 5.7L.
Looking at Fram's website, why would the 4WD K1500 have a different oil filter than the "same" engine in a C1500 2WD?
Would either of these work since the gasket sizes are different?

The Fram XG5 specs:
Gasket I.D. 3.14"
Gasket O.D. 3.56"
Gasket Thickness.25"
Gasket Usage Base
Product Height 5.17"
Product I.D. 13/16-16 Th'd
Product O.D. 3.78"

while the Fram HM3980 specs:
Gasket I.D. 2.47"
Gasket O.D. 2.75"
Gasket Thickness .19"
Gasket Usage Base
Product Height 4.94"
Product I.D. 18mmx1.5mm Th'd
Product O.D. 2.98"

 

[FFeng7]

I think the two filters have different thread sizing. The K series truck had a angled oil filter adapter to clear the front drive shaft as opposed to the C series that had an oil filter that hanged strait down.

 

[KCJeep]

Not interchangeable, one is metric one is 3/4 16 threads. Not familiar with the XG5, but the PH3980 is a very common Chevy filter, an AC Delco PF-52 equivalent.

 

[threeed1]

According to Fram's site, the XG5 fits a 1997 Chevy C1500-3500 5.7L engine

Originally Posted By: KCJeep
Not interchangeable, one is metric one is 3/4 16 threads. Not familiar with the XG5, but the PH3980 is a very common Chevy filter, an AC Delco PF-52 equivalent.

 

[MinamiKotaro]

The 4WD uses a skinnier filter so that it clears the transfer case. They're different thread sizes so you don't try to use the wrong one.