Mystery 5.3
#1
Ok...its a mystery to me anyway. Hope someone can help me.
I bought a low mileage 5.3 from a 3rd party...story was it came out of an 01 Tahoe with harness but nocomputor or accessories...paid $360. I didn't think that was bad for my area (Dallas).
I ordered a alt/ps cast alum bracket and guess what...doesn't fit....
Ok...you can slap me now for being stupid for how I have gone about this...
I really need to find out what year/donnor vehicle/model this thing really came out of. I whent to our large Chevy delership...NO help.
I took down 3 numbers I found cast and etched into the block as follows...
Cast number on passenger side top front of block...
03B06
Cast number on passenger side top rear of block...
12567392
Etched number on driver side top rear of bock...
C71110612 or C71118612
Will any of these numbers define what I have and where should I go to find out what they mean.
Before I start adding back the missing brackets and assessories I hope I will find out what I have.
All help is GREATLY appriecated...Thanks to all..

I bought a low mileage 5.3 from a 3rd party...story was it came out of an 01 Tahoe with harness but nocomputor or accessories...paid $360. I didn't think that was bad for my area (Dallas).
I ordered a alt/ps cast alum bracket and guess what...doesn't fit....
Ok...you can slap me now for being stupid for how I have gone about this...
I really need to find out what year/donnor vehicle/model this thing really came out of. I whent to our large Chevy delership...NO help.
I took down 3 numbers I found cast and etched into the block as follows...
Cast number on passenger side top front of block...
03B06
Cast number on passenger side top rear of block...
12567392
Etched number on driver side top rear of bock...
C71110612 or C71118612
Will any of these numbers define what I have and where should I go to find out what they mean.
Before I start adding back the missing brackets and assessories I hope I will find out what I have.

All help is GREATLY appriecated...Thanks to all..
#3
Joined: Jan 2006
Posts: 16,282
Likes: 438
From: Huntsville, AL
The casting number says it is an LM7, an iron 5.3, which fits what vehicle it was in.
You should be able to find parts very easily...basically anything from a 99-06 4.8/5.3/6.0 will work. Slight differences depending on what you want like injectors and intake manifolds, but all of the exterior accessories are exactly the same.
You should be able to find parts very easily...basically anything from a 99-06 4.8/5.3/6.0 will work. Slight differences depending on what you want like injectors and intake manifolds, but all of the exterior accessories are exactly the same.
#4
Wow guys that is a great start for unravaling the mystory...the heads are 706. Is there a difference between the Tahoe and truck alt/PS braket...the 06 Tahoe is a no go...btw it did have a truck intake manifold that was damaged beyond use. 
Thanks for the help....

Thanks for the help....
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