Engine Block Casting Number Identification

[GRY9273IDI]

I have some engine block casting number confusion and I’d like to get it cleared up haha.
I’ve read several posts that state the following regarding block casting numbers:
Early 6.9 IDI: 1805440C1
6.9 IDI: 1807996C1
7.3 IDI: 10809000C1
7.3 IDIT: 10809000C3

I have also read several posts and seen photos of casting numbers that are missing the first 0 in the “10809”
I am currently have 2 engine blocks in front of me and both of them have the casting number 1809000C1 not “10809”. One is a 1992 7.3 running an aftermarket ATS 093 turbo and the other is a jasper rebuilt bought second hand believed to be a 1994 with a Garrett GTP38 PN:466533-9001 turbo.

The number I have found is located under the oil cooler and tucked right above the motor mount.

Maybe we can get all the block casting number info down in this post and then just pin it to the tech forums since it appears to be a common question.

 

[GRY9273IDI]

Trying to keep this thread alive… Does anyone have any info to help clear this up?

 

[FrozenMerc]

Those are Navistar part numbers, most likely for the raw casting, and not for the finished machined part. It was/is typical to change the part number for each revision that the part undergoes. The missing 0 could be anything from a different version of the casting for a specific application to a foundry mistake. Without the engineering drawings or a proper bill of material, they don't mean much.

 

[IDIBRONCO]

I think that most people are more interested in the serial numbers than they are the casting numbers.