So the title:
"WWII GMC CCKW Military Senior Complete Oil Filter, G-508"
Here is a partial screencap for historical reference:
Ok.
One would think that this is an AC type S-2 oil filter. No. I'm not sure how the lid got labeled AC S-2 as the domed portion of the lid is the wrong profile.
Here is the profile of an S-2 lid:
Note it is COMPLETELY difference from an S-2 lid.
This is the lid in the ebay auction:
This is the lid for an SC-660:
Note the dome shape, as in the auction.
Note that the SC-660 can be decoded as follows:
Type SC-650 was an "S" line filter. The "C" denoted it was a tailored kit packaged specifically for Chevrolet applications. (Kits tailor made for Cadillac used a "K"; "P" for Dodge, Chrysler and Plymouth applications; "M" for Oldsmobile; "F" for Ford; "N" for Nash). The "6" denoted the line type. The "50" established what model year it was first put into service. So, SC-650 was an S-6 type, tailor made for Chevrolet, and first introduced in 1950. This same referencing applied to other types as well, such as the S-2 line.
This is for a lid for a 1960 SC-260 (2 quart version of the S-660 above:
Referencing this:
SC-660 Series
Beginning in 1960, the unit used would now be Chevrolet number 5576528, which is AC type SC-660. (See image #37 - 5576528/SC-660 unit.) This unit was exactly the same as the 1959 model SC-659 in physical appearance and lettering with the exception that the inlet line connection was on the firewall side of the filter (as installed), whereas the 1959 version connected on the inner fender side (as installed). The top, and the lettering on it was exactly the same as the 1959 version. (See image #36)
The SC-660 filter type was used on the 1960, 1961, and 1962 Chevrolet 235's as well as the two quart SC-260 unit described below. They were both discontinued for 1963 since the newly introduced Chevrolet 230 cubic inch 6 cylinder engine now used a spin on type element, eliminating the need for this bolt-on type style. The one exception to this is the 1963 Chevrolet 4 wheel drive trucks which retained the 235 engine until mid-year 1963. Once the 235 was finally phased out, so were bolt-on oil filter units for use on Chevrolet cars and trucks from that point forward.
The ebay auction clearly shows the manufacturer part number as 5570141, not the original S-2 part number of 1504439 or the CCKW part number 1504314 (TM10-1562).
Also, every one of the the stock numbers on the decal are post WWII/Korea. The FSN is actually an NSN (FSNs did not have the NCBC.. the -00- after the first 4 digits) and they were all converted by 30 September 1974.
All of this is redundant as the biggest issue is: The lid is not stamped 'Use Military Senior Oil Filter' on the rim, only 'Heavy Duty' filter. Because, well, it never was a CCKW oil filter.
This is a GSA sourced item for non-DoD equipment procured in the 50's and 60's. It never would have been installed or even purchased for the War Department (pre-1947), the US Army, or the Department of Defense (post 1949).
