Blue Ox Serial Number Label: SSteve: Toads and Motorhome Related Towing: 5: 04:41 AM: Locating My C7 Serial Number: Gadget Man: Caterpillar Engine Forum: 6: 02:52 AM: CAT Engine Serial Number: amandah: Winnebago Industries Owner's Forum: 3: 04:15 PM: Allison serial number: footdoc: Newmar Owner's Forum: 5: 01. Caterpillar:3304,3306 Series: Cat 3306 Engine Number Location: waltini: 8: 3: 13-Jun-19 Original Post: 05-Jun-19: I have just purchased a timber cruiser built in 1985 still with its original 3306 turbo engine. The identification plaque has long gone but I believe that Caterpillar stamped the engine/serial number some where on the block.

Dates of castings can be found on engine blocks,cylinder heads final drive casings etc.
This is a guide to decipher the casting codes.
N U M E R A L K O D
0 1 2 3 4 5 6 7 8 9
N = 0 K = 7
U =1 0= 8
M= 2 D = 9
E= 3
R = 4
A = 5
L = 6
If there are 6 letters on the casting it is the day,month and year that that piece was made.
Eg
U would be 1 M would be 2 (12)
U would be 1, N would be 0 (10)
K would be 7,D would be 9 (79)

Cat Motor Serial Number Lookup Numbers

There are 6 letters so I would know the date is 12-10-79 or 12th Oct 1979
If it has 4 letters it would be month and year of manufacture.

Cat Motor Serial Number Lookup Reverse

Hope this makes sense

Caterpillar Serial Number Lookup

Martyn