2004 Pontiac GTO
Thread Starter
Registered User
Joined: Sep 2021
Posts: 2
Likes: 0
2004 Pontiac GTO Hello Everyone,
I am in need of some assistance in locating where an engine code number would be located on a LS1 5.7L that is in a 2004 Pontiac GTO. Any quick help would be greatly appreciated
Thanks
I am in need of some assistance in locating where an engine code number would be located on a LS1 5.7L that is in a 2004 Pontiac GTO. Any quick help would be greatly appreciated
Thanks
TECH Enthusiast
Joined: Mar 2005
Posts: 663
Likes: 384
From: South Carolina
To add...
Besides the displacement number on the block you can find the engines manufacture date to see if it corresponds with the vehicles model year. If it's off the engine has probably been replaced. That said vehicles manufactured from August through December are usually the next model year.
The letter/numbers cast into the block under the head at the front of bank 2 are the manufacture date.
K134 = November 13th 2004 on my LQ9 that came from a 2005 Escalade.
Attachment 712605
Besides the displacement number on the block you can find the engines manufacture date to see if it corresponds with the vehicles model year. If it's off the engine has probably been replaced. That said vehicles manufactured from August through December are usually the next model year.
The letter/numbers cast into the block under the head at the front of bank 2 are the manufacture date.
K134 = November 13th 2004 on my LQ9 that came from a 2005 Escalade.
Attachment 712605
TECH Addict
Joined: Dec 2017
Posts: 2,182
Likes: 970
Those stampings are notoriously useless when a swap is involved, because they aren't changed when anything about the motor is changed. You have NO WAY of knowing that. Somebody could have taken a 99 LS1 out of a Firebird, put 243 heads and a Titan 3 cam in it, done who knows what to the bottom end, and the stamping will STILL say ... 99 LS1 out of a Firebird.
A better way to approach this might be, to go DIRECTLY to the thing you actually want to know, such that you can extract useful, actionable, accurate information on which you can reliably base a decision. The stamping code IS NOT that. What is it you REALLY want to know, that you think that code will tell you? What will you do differently depending on what that code would tell you?
A better way to approach this might be, to go DIRECTLY to the thing you actually want to know, such that you can extract useful, actionable, accurate information on which you can reliably base a decision. The stamping code IS NOT that. What is it you REALLY want to know, that you think that code will tell you? What will you do differently depending on what that code would tell you?
Teching In
Joined: Nov 2018
Posts: 15
Likes: 2
I just had the engine out of my Corvette. It turns out that there are many different ways to identify what engine you have and what year it is and what it most likely came from. The engine block code will not tell you everything.
As it would turn out the engine from my C5 was in fact most likely swapped in from a 2004 GTO or an '04 C5. I identified this based on the block itself, the Gen 4 rods in it, the style of camshaft gears, and the cylinder head bolts required. A thing to note, though, things like the heads and cam shaft gears are not necessarily good identifiers as they are easily changed for various reasons. Knowing that the revised bolt pattern was introduced in late '04, as well as having press fit Gen 4 rods with Gen 3 pistons, were the only true identifiers I had.
What are you trying to figure out, specifically? Because simply looking at the code or bullseyes on the block to identify LS1 block or LS6 block will not tell you the entire story.
As it would turn out the engine from my C5 was in fact most likely swapped in from a 2004 GTO or an '04 C5. I identified this based on the block itself, the Gen 4 rods in it, the style of camshaft gears, and the cylinder head bolts required. A thing to note, though, things like the heads and cam shaft gears are not necessarily good identifiers as they are easily changed for various reasons. Knowing that the revised bolt pattern was introduced in late '04, as well as having press fit Gen 4 rods with Gen 3 pistons, were the only true identifiers I had.
What are you trying to figure out, specifically? Because simply looking at the code or bullseyes on the block to identify LS1 block or LS6 block will not tell you the entire story.
Last edited by Ken-02Z28A4; Sep 4, 2021 at 11:09 AM.
Thread Starter
Registered User
Joined: Sep 2021
Posts: 2
Likes: 0
Thank you all for the answers. I am sorry I was not more clear. Essentially, I am trying to find the location of the engine's "serial" number so to speak. I.E. in new GM models, there is a VIN derivative on the upper portion of the block on the driver side, right by the firewall. the last 6 digits of this 9 digit code is the last 6 digits of the VIN. What I have an engine serial number, or partial number, from GM that corresponds to the specific LS1 engine that was inside of a 2004 GTO. I just need the location of where that number should be on the engine, as GM was not much help and getting that number was like pulling teeth. I am not talking about the manufacture date, the block size or if its a 5.7 or 6.0.
Hope this clears up what I am talking about. If there are any further questions, please feel free to PM me.
thanks
Hope this clears up what I am talking about. If there are any further questions, please feel free to PM me.
thanks
TECH Addict
Joined: Dec 2017
Posts: 2,182
Likes: 970
Let me reiterate:
A swapped-in motor is not likely to be "all-original". Therefore the stamping code, EVEN IF you could "decode" it down to the individual vehicle it came from, is not likely to tell you the whole truth about it. It is more likely to lead you astray in unpredictable directions. It is USELESS.
Given the overall uselessness of the stamping code, if we knew WHY you wanted to know this, we might be able to tell you some way to find THAT out, independent of "codes".
A swapped-in motor is not likely to be "all-original". Therefore the stamping code, EVEN IF you could "decode" it down to the individual vehicle it came from, is not likely to tell you the whole truth about it. It is more likely to lead you astray in unpredictable directions. It is USELESS.
What will you do differently depending on what that code would tell you?
