Hello everyone, this is my first post, I'm about to become a member of the diesel family...I am buying a 2005 Pony Xpress RV,Chevy 5500 chassis with the Duramax/Allison combo. The 8th number on the vin is 2, but how do I tell if its the early version with 590 torque, or the later version with 605?

I think that the 10th digit will tell you.....if its a 4 then its a 2004 and if its a 5 then its a 2005

If its got the most recent updates or calibrations from GM, they'll both end up with 605, regardless if its an 04.5 or 05.

If its got the most recent updates or calibrations from GM, they'll both end up with 605, regardless if its an 04.5 or 05.

I am a new owber of a 05 3500 should i check with dealer about the updates and if so what does the update do? Any help with fuel MPG?

I think that the 10th digit will tell you.....if its a 4 then its a 2004 and if its a 5 then its a 2005

Thanks skyhigh, you are right, when you said you "think", I did some more research and came up with this info:

Example: 1GCHK29143Exxxxxx for LB7 and 1GCHK29245Exxxxx for LLY. It is important to know this as while the engines are essentially the same at the core, the electronics, turbochargers, electronics, and injectors are different among the variants. The 10th place in the VIN number identifies the model year on these vehicles. The example above shows the 2003 model year LB7 and 2005 LLY.

The RV I am buying has an '05 LLY, the 10th digit in its vin is 5
thanks for the help!

I am a new owber of a 05 3500 should i check with dealer about the updates and if so what does the update do? Any help with fuel MPG?

Mileage? Doubtful. Some of these trucks get awesome mileage and others, terrible. There seems to be no two alike.

I would go to the dealer and see if its had the latest GM calibrations. I would think it has. If the truck's ever been to the dealer for anything, since 2005, its gonna have them regardless if you asked for them or not. Its automatic. The dealerships probably wont know that this update (that came out 3 years ago) had anything to do with bumping the numbers up. I had a programmer for my 04.5 LLY and after getting the truck back home, the tuner wouldnt work. I had to call the dealership to make some story up about how I have a "Scan tool" and I'm able to read codes with it. They said that they installed the latest update.

So, I would think that you have the latest and greatest since this calibration came out 3 years ago. There have been many more since then so I would think you're ok.