Controversy in engine block decoding
 

So I found the engine code for my truck. It's a 81 pickup. The block is numbers matching. I found the Vin stamped with the engine code. The engine code is T0311UDB. This makes no sense because it's numbers matching but this engine code UDB says it's a 83 305. Anyone come across this?

Re: Controversy in engine block decoding
 

Did you happen to look up the suffix code on the www.nastyz28.com website by any chance? If so, their listing only shows the final year "FY" that a particular code was used.

So that year listing is just saying the "UDB" suffix code was last used in 1983, not that it's an 83 engine.

Re: Controversy in engine block decoding
 

Ok that makes sense now. I was on nastyz28.com for the decoding and They didnt get into much detail on their site about the year codes.

Re: Controversy in engine block decoding
 

Check the casting date behind the pass side head on the bellhousing flange. The last number is the year your motor was built.