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My apologies for such a rookie question but I'd like to know how I can physically identify an L33 motor.
I know the internal differences but I'm looking at one tomorrow and want to make sure it is in fact an L33 and not an LM7 or any of the other 5.3s. Aside from the VIN of the truck it came out of, all I know that I can look for are the heads, which should be 799s or 843s.
Anyone have any other tips on how I can identify it?
LM7 will have a cast iron block, L33 will have an aluminum block. Most have 700 heads, some have 243s, and I've heard that a few have one of each..... Most of them that I've seen also have the round coils with heak sinks. Here's a couple of pics of mine, if it helps you.
And, like mentioned before, the L33 has the knock sensors in the intake valley. Gen 4 engines have the knock sensors on the sides of the block, near the engine mounts.
Sorry all, one last question. The easiest way to distinguish the L33 from say an LH6 is the reluctor wheel sensor, right? The L33 will have a black one for the 24X and the LH6 will have a gray one for 58X, correct?
Or, since the intake manifold and accessories are on the motor if I can't see the knock sensors on the sides of the block then it's an L33, correct? Because the LH6 carries them on the sides of the block where the L33 carries them down in the valley?
Sorry all for the rookie questions. There is so much info floating around it makes my head spin. I am learning a lot though and this forum is seriously invaluable! Great source on info!
EDIT: After poking around some more it looks like the MAP sensor will be on the back of the intake manifold on the L33.
If your not sure , post a pic of it for us and we will identify it to the best of our knowlege. AK hit it right though, if your not sure after all that like i said post a pic.
One other resort is to pull a head off and it will have flat top pistons.
But its hard to miss an alum engine block , your worrying too much!
Ok...so I realize this is an older thread but one that I came across in my quest to understand what I might have found sitting in a shed. I think I found an L33 because it IS an aluminum block and it does have a rear sump oil pan. However the intake and fuel rails are different from others I’ve seen. Anyone tell from these pics what I’m looking at here??
Thats a Gen 4 5.3, not the L33. That has DOD and a different cam than the L33 does. I can tell it has DOD by the valley cover, and I know its a Gen 4 by the intake. The L33 has the 78mm intake and your engine has the 87mm intake.
The rotating assembly is essentially exactly the same between the 2.
03-14-2012, 11:47 AM
How to identify an L33
