How to tell the difference in a 2007 silverado transmission from class

[weather]

Ok, here's my dilema. I aquired a 2003 chevy astro van lt, that has a 2007 4.3L silverado motor in it. I need the trannie replaced. I see imprinted on the side of the trannie, a big 07 imprinted on it. But in 07, the transmission changed electronically, do when they at the salvage yards ask, do I have the classic or new style silverado, I can't tell what the trannie is from. I'm thinking it's the classic style, since that's not the newer style, which goes from 2007 and up, with the classic from 2007 and earlier models of the silverado, so I'm hoping someone here can help me towards that decision on getting a used trannie. Don't want a rebuild because 8 can ge in and out if the shop in one day with a low miles used trannie

[Jsdirt]

I'm pretty sure the pan isn't going to tell you much, since the same basic frame of the 4L60E has been around since 1987 or so as the 700r4. Only difference was the addition of electronics in '96 for OBD-II, as far as I know.

 

The VIN from the donor vehicle should point you in the right direction. Can enter it in any site like Carfax, or NHTSA, or Kelly BB - should give a description of the vehicle from the VIN. Anything LT, LT2 or LTZ is NEW body.

 

Just another way to go about it. There's probably better ways, but this is how I identify vehicles that can't be ID'ed due to damage, or being parted out.

 

I would say the best way to ID that trans would be by the wiring harness. I'm willing to bet the new body has 10x the amount of wiring as the Classic, or prior year models.

[Heavy 5.7]

Don't worry about numbers cast into the housing, identify it by the oil pan shape:

http://www.roadkillcustoms.com/hot-rods-rat-rods/garage-shop-reference-Transmission-Identification.asp