How can you tell what year motor it is?

[bobwire]

We just put a 6.5 TD in my HMMWV and trying to figure out what year it is.
Serial# reference? Casting marks?
Anybody know?

 

[NDT]

Did you new engine come from a scrapped HMMWV or a GM van?

 

[Lionel]

Passenger side, rear of motor, just behind the head. Should look like either a letter followed by three numbers (B217), two pairs of numbers followed by a letter (03 17 S), or blank. What do you have?

 

[Action]

Also look at the tag on the stainless oil pressure line or the voltage regulator. They should be close to the motor year.

 

[bobwire]

It came from a HMMWV.

its hard to see but it looks like 03 10 N

The voltage regulator is not original

 

[NDT]

You are golden, from a HMMWV is all that matters, you have a GEP engine. 2005 and newer.

 

[Lionel]

Ok. 03 10 N would be a GEP from March 10, 2005. Its a good block.

 

[bobwire]

Great, Thank you guys,

Curious what makes N signify 2005?

 

[Lionel]

H is the first GEP year which is 2000, there is no I and no O. N = 2005. Newest surplused or salvaged I've come across were S blocks.