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is it possible to hook a lbz tranny to a lb7 motor? my buddy has the lbz tranny and my tranny is hurtin and i didnt noif the swap was possible
 

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No, it's not that easy. The LB7 used a 5 speed Allison with 3rd GEN controls. The LBZ uses a 6 speed Allison with 4th GEN controls. There are big long threads here about turning a five speed truck into a six speed. I suggest you take a look at them before you start this project.
 

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In theory, you MIGHT be able to swap the transmission in IF you put the LB7 valve body, internal harness and NSBU into the newer transmission, but IIRC, the LLY and newer Allisons have different size transmission cooler lines. I can assure you the 6 speed TCM will not communicate with the LB7 or LLY ECM, at best causing loss of comms codes and harsh shifting in the TCM's "default" mode with no torque converter lockup, or a no-start at worst.
 
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