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Discussion Starter #1
Got an 06 LBZ block with LLY tuning in a medium duty platform.

I'm looking at an 07 and I don't know if there is a serial number, or manufacture date or what constitutes the boundary for 07.5 and the change from LBZ to LMM.

And are additional EPA additions for the LMM platform something that might be preferable to avoid if I'm looking at a couple relatively equivalent trucks on either side of that LBZ / LMM threshold.

I'm looking as late as '08 so I may just be in for it and ultimately following on relevant deletes -- and I think there are some of those relevant for the earlier platform anyway, but in my first purchase I followed the discussions here that focused on the improvements on the LBZ block and that lead me to a preference for '06 trucks over '04 and '05, so I'm coming back to the well.

I've been VERY satisfied with the '06 and just from a simplicity sake I'd be into having two trucks that have the same setup, but you don't always find all the options, the right body, etc. on just the serial number range you're after so I'm trying to figure out, other than trying to match the set-up I have so that my maintenance program and knowledge can be parallel, if there are design preferences that should encourage me even more strongly to stay in the LBZ era.

Because the medium duties didn't have the same issue with air intakes in '04 and '05 I haven't written those off either. So if I were to go outside my '06 comfort zone, I'm certainly open to having folks encourage me to go back in time rather than forward.

I'm sure there is no 'right' answer to these questions but the wealth of experience here has pointed me in directions before and I'm eager to here what folks have to say from their personal experiences.

thanks,

brian
 

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Check the 8th digit of the vin :

1= LB7
2= LLY
D= LBZ
6= LMM

I love my lmm, have had no problems with it. But I would love to have an lbz, then you don't have to deal with the emmisions shit.
 

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I believe the OP is just talking about the block.... not the actual truck.

engine blocks don't have a vin.
 

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Hmm.. It does seem that way now that I read it more carefully. But then he said something about wanting to have 2 similar trucks. So now I don't know haha
 

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Iirc, the short block is very similar if not the same between a lbz and lmm.
The internals are the same, injectors and turbo I dont think are, also the lmm has a dpf And the ECM is different (not positive). The egr is the same i think.
They are almost identical, but the lbz motor is equipped with less emissions stuff and a louder turbo:thumb
 

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And what I'm getting from the op's statement is that he has an 06lly which is in fact a detuned lbz, and that is in a medium duty such a a 4500 or 5500.
 

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Was going to say check the body style... but then I realized what you were talking about.

If it has DPF its a LMM, if not... Its a lbz
 

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Discussion Starter #9
that's right

And what I'm getting from the op's statement is that he has an 06lly which is in fact a detuned lbz, and that is in a medium duty such a a 4500 or 5500.
the serial number for the truck I have has the "2" and the build sheet lists LLY but the block is the later block with the larger EGR size (that's how I was able to identify which block I had).

So from all the responses -- thanks -- I so far got that the block was not changed significantly if at all between the LBZ and LMM. For that matter, I don't know if they ever put the LBZ as such into the medium duty platform but essentially the 06 to 07.5 mediums duties have an LLY tune on the block that was used for the LBZ (I believe, stand to be corrected).

Anyway, the question which has been brought up a little is, how desirable it would be to stay in the LBZ/LLY o6 to 07.5 years vs. the later tune and emissions package.

I don't mind the the louder turbo. So the real question is whether any of the late model, e.g. 07.5 and later, emissions controls would make you shy away from that generation if you could.

thanks,

brian
 

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Discussion Starter #10
Check the 8th digit of the vin :

1= LB7
2= LLY
D= LBZ
6= LMM

I love my lmm, have had no problems with it. But I would love to have an lbz, then you don't have to deal with the emmisions shit.
so checked the VINS, on the medium duty the 8th digit is a 9. So I wonder what the heck that means. MAybe a medium duty tuned version of the LMM?

anyone got the secret code?

thanks,

brian
 

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Blocks are the same, the emissions requirements will be dictated by the ecm selection you make and the model year truck in which you choose to install it in.
 

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If you have the vin I can make it easy and run it. Also if its just the block and has the adapter housing. Check on the backside by the oil filter housing areas for 8 numbers and letters mixed also can be on starter side if it has the trans on it numbers will be there also. They will look very werd small little dots making numbers and letters this is how we mark the motor and trans at the factory.
 
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