OK so I picked up a motor from buddy of mine said it was 5.3 with 4l60 when I picked it up I seen the trans was a 6l80 but motor I'm not sure a little input would be awesome!!

 

What number does it say on the front of the block?

 

With all accessiores on I couldn't see where would it be

 

What casting number is on the heads?

 

799 and also can anyone confirm this being 6l80

 

that sure looks like a 6l80e to me, and the 799 heads along with the block number give it away as a 5.3 gen IV engine

 

The numbers in the last photo indicate it's a 4.8 engine. I'm pretty sure GM starting mating the 4.8L engine with 6L90 transmission starting in 2010 in vans & pickup trucks.

You need to find a tag or laser etching on the rear of the block just below the head on the driver's side to confirm.

http://engineguy.com/general-motors/...crc-vin-c.html